0001871509-21-000009 | 10-Q | XBRL Viewer

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COVER PAGE - shares	9 Months Ended
COVER PAGE - shares	Sep. 26, 2021	Nov. 11, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 26, 2021
Document Transition Report	false
Entity File Number	001-40951
Entity Registrant Name	PORTILLO'S INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	87-1104304
Entity Address, Address Line One	2001 Spring Road
Entity Address, Address Line Two	Suite 400
Entity Address, City or Town	Oak Brook
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60523
City Area Code	630
Local Phone Number	954-3773
Title of 12(b) Security	Class A common stock, $0.01 par value per share
Trading Symbol	PTLO
Security Exchange Name	NASDAQ
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding (in shares)		35,807,171
Entity Central Index Key	0001871509
Amendment Flag	false
Current Fiscal Year End Date	--12-26
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3

CONDENSED BALANCE SHEETS (UNAUDITED) $ in Thousands	Sep. 26, 2021 USD ($)
Cash and cash equivalents	$ 49,367
Total assets	929,462
COMMITMENTS AND CONTINGENCIES (NOTE 12)
COMMON EQUITY:
Class A common stock, par value 0.01 per share, 100 shares authorized, 100 issued and outstanding	0
Additional paid-in-capital	141,751
Total common equity	145,177
Portillo's Inc.
Cash and cash equivalents	1
Total assets	1
COMMON EQUITY:
Class A common stock, par value 0.01 per share, 100 shares authorized, 100 issued and outstanding	0
Additional paid-in-capital	1
Total common equity	$ 1

- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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CONDENSED BALANCE SHEETS (UNAUDITED) (Parenthetical) - $ / shares	Sep. 26, 2021	Aug. 11, 2021	Dec. 27, 2020
Common stock, par value (in dollars per share)	$ 0.01
Common units authorized (in shares)	51,210,222		51,192,434
Common units issued (in shares)	51,210,222		51,192,434
Common units outstanding (in shares)	51,210,222		51,192,434
Portillo's Inc.
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common units authorized (in shares)	100
Common units issued (in shares)	100	100
Common units outstanding (in shares)	100

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Sep. 26, 2021	Dec. 27, 2020
CURRENT ASSETS:
Cash and cash equivalents	$ 49,367	$ 41,211
Restricted cash	190	221
Accounts receivable	5,727	5,204
Inventory	4,399	5,075
Other current assets	7,445	2,915
Total current assets	67,128	54,626
Property and equipment, net	186,621	174,769
OTHER ASSETS:
Goodwill	394,298	394,298
Intangible assets-net of accumulated amortization	260,541	266,180
Equity method investment	16,278	16,015
Other assets	4,596	4,334
Total other assets	675,713	680,827
Total assets	929,462	910,222
CURRENT LIABILITIES:
Accounts payable	21,531	21,427
Current portion of long-term debt	3,324	3,324
Current deferred revenue	3,929	6,774
Accrued expenses	33,482	34,827
Total current liabilities	62,266	66,352
LONG-TERM LIABILITIES:
Long-term debt, net of current portion	466,764	466,380
Deferred rent	30,844	26,694
Other long-term liabilities	6,862	9,516
Total long-term liabilities	504,470	502,590
Total liabilities	566,736	568,942
COMMITMENTS AND CONTINGENCIES (NOTE 12)
Redeemable preferred units, value	217,549	200,571
COMMON EQUITY:
Common units—51,210,222 and 51,192,434 units authorized, 51,210,222 and 51,192,434 units issued and outstanding as of September 26, 2021 and December 27, 2020	0	0
Stock subscription receivable	0	(499)
Additional paid-in-capital	141,751	141,208
Retained earnings	3,426	0
Total common equity	145,177	140,709
Total liabilities and members' equity	$ 929,462	$ 910,222

CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) - $ / shares	Sep. 26, 2021	Dec. 27, 2020
Common stock, par value (in dollars per share)	$ 0.01
Common units authorized (in shares)	51,210,222	51,192,434
Common units issued (in shares)	51,210,222	51,192,434
Common units outstanding (in shares)	51,210,222	51,192,434

CONDENSED CONSOLIDATED STATEMENT OF OPERATIONS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Income Statement [Abstract]
REVENUES	$ 138,003	$ 119,700	$ 396,044	$ 336,960
Restaurant operating expenses:
Cost of goods sold, excluding depreciation and amortization	44,285	36,572	121,465	106,095
Labor	36,921	29,125	102,433	87,205
Occupancy	7,000	6,368	20,890	18,717
Other operating expenses	15,554	13,012	44,187	37,559
Costs and Expenses	103,760	85,077	288,975	249,576
General and administrative expenses	11,750	9,706	35,755	27,918
Pre-opening expenses	347	544	2,307	838
Depreciation and amortization	5,516	6,138	18,225	18,404
Net income attributable to equity method investment	(292)	(121)	(651)	(353)
Other income, net	(292)	(514)	(1,095)	(1,092)
OPERATING INCOME	17,214	18,870	52,528	41,669
Interest expense	10,683	10,766	32,124	34,298
Net income (loss) attributable to common unit holders	6,531	8,104	20,404	7,371
Less: Redeemable preferred units accretion	(5,886)	(5,282)	(16,978)	(15,240)
Net income (loss) attributable to common unit holders	$ 645	$ 2,822	$ 3,426	$ (7,869)
Earnings/(loss) per common unit:
Basic (in dollars per share)	$ 0.01	$ 0.06	$ 0.07	$ (0.15)
Diluted (in dollars per share)	$ 0.01	$ 0.05	$ 0.07	$ (0.15)
Weighted-average common units outstanding:
Basic (in shares)	51,210,222	51,192,285	51,201,100	51,187,878
Diluted (in shares)	51,581,685	51,410,002	51,569,034	51,187,878

CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN REDEEMABLE PREFERRED UNITS AND EQUITY (UNAUDITED) - USD ($) $ in Thousands	Total	Preferred Units	Common Units	Stock Subscription Receivable	Additional Paid-In Capital	Retained Earnings
Beginning balance (in shares) at Dec. 29, 2019		100,000
Beginning balance at Dec. 29, 2019		$ 180,047
Preferred Units
Redeemable preferred units accretion		$ 15,240
Ending balance (in shares) at Sep. 27, 2020	100,000	100,000
Ending balance at Sep. 27, 2020	$ 195,287	$ 195,287
Beginning balance (in shares) at Dec. 29, 2019			51,185,674
Beginning balance at Dec. 29, 2019	147,734		$ 0	$ (749)	$ 148,483	$ 0
Common Units
Net income	7,371					7,371
Unit-based compensation	564				564
Repayment of subscription receivable	250			250
Issuance of common units (in shares)			6,760
Issuance of common units	25				25
Redeemable preferred units accretion	(15,240)				(9,958)	(5,282)
Ending balance (in shares) at Sep. 27, 2020			51,192,434
Ending balance at Sep. 27, 2020	$ 140,704		$ 0	(499)	139,114	2,089
Beginning balance (in shares) at Jun. 28, 2020	100,000
Beginning balance at Jun. 28, 2020	$ 190,005
Preferred Units
Redeemable preferred units accretion	$ 5,282
Ending balance (in shares) at Sep. 27, 2020	100,000	100,000
Ending balance at Sep. 27, 2020	$ 195,287	$ 195,287
Beginning balance (in shares) at Jun. 28, 2020			51,185,674
Beginning balance at Jun. 28, 2020	137,670		$ 0	(499)	138,902	(733)
Common Units
Net income	8,104					8,104
Unit-based compensation	187				187
Issuance of common units (in shares)			6,760
Issuance of common units	25				25
Redeemable preferred units accretion	(5,282)					(5,282)
Ending balance (in shares) at Sep. 27, 2020			51,192,434
Ending balance at Sep. 27, 2020	140,704		$ 0	(499)	139,114	2,089
Beginning balance (in shares) at Dec. 27, 2020		100,000
Beginning balance at Dec. 27, 2020	$ 200,571	$ 200,571
Preferred Units
Redeemable preferred units accretion		$ 16,978
Ending balance (in shares) at Sep. 26, 2021	100,000	100,000
Ending balance at Sep. 26, 2021	$ 217,549	$ 217,549
Beginning balance (in shares) at Dec. 27, 2020			51,192,434
Beginning balance at Dec. 27, 2020	140,709		$ 0	(499)	141,208	0
Common Units
Net income	20,404					20,404
Unit-based compensation	443				443
Repayment of subscription receivable	499			499
Issuance of common units (in shares)			17,789
Issuance of common units	100				100
Redeemable preferred units accretion	(16,978)					(16,978)
Ending balance (in shares) at Sep. 26, 2021			51,210,223
Ending balance at Sep. 26, 2021	$ 145,177		$ 0	0	141,751	3,426
Beginning balance (in shares) at Jun. 27, 2021	100,000
Beginning balance at Jun. 27, 2021	$ 211,663
Preferred Units
Redeemable preferred units accretion	$ 5,886
Ending balance (in shares) at Sep. 26, 2021	100,000	100,000
Ending balance at Sep. 26, 2021	$ 217,549	$ 217,549
Beginning balance (in shares) at Jun. 27, 2021			51,210,223
Beginning balance at Jun. 27, 2021	144,113		$ 0	(249)	141,581	2,781
Common Units
Net income	6,531					6,531
Unit-based compensation	170				170
Repayment of subscription receivable	249			249
Redeemable preferred units accretion	(5,886)					(5,886)
Ending balance (in shares) at Sep. 26, 2021			51,210,223
Ending balance at Sep. 26, 2021	$ 145,177		$ 0	$ 0	$ 141,751	$ 3,426

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 20,404	$ 7,371
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	18,225	18,404
Amortization of debt issuance costs and discount	2,877	2,901
Loss on sales of assets	130	19
Unit-based compensation	443	564
Deferred rent and tenant allowance	3,099	2,726
Amortization of deferred lease incentives	(289)	(241)
Gift card breakage	(554)	(556)
Changes in operating assets and liabilities:
Accounts receivables	(89)	804
Receivables from related parties	(144)	204
Inventory	676	83
Other current assets	807	572
Accounts payable	(2,511)	(881)
Accrued expenses and other liabilities	(3,634)	583
Deferred lease incentives	690	1,976
Other assets and liabilities	(239)	3,576
NET CASH PROVIDED BY OPERATING ACTIVITIES	39,891	38,105
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(27,687)	(10,138)
Purchase of investment securities	(200)	0
Proceeds from the sale of property and equipment	123	30
NET CASH USED IN INVESTING ACTIVITIES	(27,764)	(10,108)
CASH FLOWS FROM FINANCING ACTIVITIES:
Repayments of short-term debt	0	(15,000)
Payments of long-term debt	(2,493)	(12,493)
Proceeds from Paycheck Protection Program loan	0	10,000
Proceeds from issuance of common units	100	25
Repayment of stock subscription receivable	499	250
Payments for in-process equity financings (offering costs)	(2,108)	0
NET CASH USED IN FINANCING ACTIVITIES	(4,002)	(17,218)
NET INCREASE IN CASH AND CASH EQUIVALENTS AND RESTRICTED CASH	8,125	10,779
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT BEGINNING OF THE PERIOD	41,432	22,629
CASH AND CASH EQUIVALENTS AND RESTRICTED CASH AT END OF THE PERIOD	49,557	33,408
SUPPLEMENTAL CASH FLOW INFORMATION
Interest paid	29,043	24,468
NON-CASH INVESTING AND FINANCING ACTIVITIES:
Accrued capital expenditures	2,041	3,411
Proceeds from the sale of property and equipment	41	61
Redeemable preferred units accretion	(16,978)	(15,240)
Deferred offering costs in accounts payable	$ 2,446	$ 0

STOCKHOLDERS' EQUITY	9 Months Ended
STOCKHOLDERS' EQUITY	Sep. 26, 2021
Equity [Abstract]
STOCKHOLDERS' EQUITY	STOCKHOLDERS' EQUITYOn August 11, 2021, the Company issued 100 shares of common stock to Portillo’s OpCo for $1,000. The excess paid over par value of $0.01 per share was recorded to additional paid-in capital.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details

DESCRIPTION OF BUSINESS	9 Months Ended
DESCRIPTION OF BUSINESS	Sep. 26, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF BUSINESS	DESCRIPTION OF BUSINESSPortillo’s Inc. (the “Company’) was formed and incorporated as a Delaware corporation on June 8, 2021. The Company was formed for the purpose of completing a public offering and related reorganization transactions (collectively, the "Transactions”) in order to carry on the business of PHD Group Holdings LLC and its subsidiaries (“Portillo’s OpCo”). Following the consummation of the Transactions on October 20, 2021, the Company became the sole managing member of Portillo’s OpCo and has the sole voting interest in, and controls the management of, Portillo’s OpCo. See Note 4 for more information. As of September 26, 2021, the Company had not yet commenced operations. All activities for the period from June 8, 2021 through September 26, 2021 relates to the Company's formation and the preparation for the initial public offering ("IPO"), which is described below. DESCRIPTION OF BUSINESS Portillo’s Inc. was formed and incorporated as a Delaware corporation on June 8, 2021. The Company was formed for the purpose of completing a public offering and related reorganization transactions in order to carry on the business of PHD Group Holdings LLC and its subsidiaries. Unless the context otherwise requires, references to "we," "us," "our," "Portillo's," and the "Company" refer to Portillo's Inc. and its subsidiaries, including PHD Group Holdings LLC, which we refer to as "Portillo's OpCo".We operate fast-casual restaurants in Illinois, Indiana, California, Arizona, Florida, Wisconsin, Minnesota, Iowa and Michigan, along with two food production commissaries in Illinois. As of September 26, 2021 and December 27, 2020, the Company had 66 and 63 restaurants in operation, respectively. The Company also had 3 and 4 non-traditional locations in operation as of September 26, 2021 and September 27, 2020, respectively. These non-traditional locations include a food truck, ghost kitchen (small kitchen with no store-front presence, used to fill online orders), and concessions. Portillo's Hot Dogs, LLC additionally has a 50% interest in a single restaurant in Chicago, IL, that is referred to in Note 8. There were no restaurant closings during any period presented in the financial statements. The Company’s principal corporate offices are located in Oak Brook, IL.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	Sep. 26, 2021
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying condensed balance sheet is presented in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The preparation of the financial statement in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statement. Separate statements of operations, changes in stockholders' equity, and cash flows have not been presented because the Company has not engaged in any business or other activities other than the initial issuance of Class A common stock, par value $0.01 per share ("Class A common stock"). Fiscal Year The Company uses a 52- or 53-week fiscal year ending on the Sunday prior to December 31. In a 52-week fiscal year, each quarterly period is comprised of 13 weeks. The additional week in a 53-week fiscal year is added to the fourth quarter. Offering Costs In connection with the IPO, Portillo's OpCo incurred certain legal, accounting, and other IPO-related costs, which were reimbursed by the Company upon the consummation of the IPO. Such costs are deferred and recorded in stockholders’ equity as reduction from the proceeds of the offer. As of September 26, 2021, $4.6 million of deferred offering costs had been recorded. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") for interim financial information. The Company has prepared the accompanying unaudited condensed consolidated financial statements in accordance with GAAP for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission (the "SEC"). In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments necessary for a fair presentation of our financial position and results of operations. Interim results of operations are not necessarily indicative of the results that may be achieved for the full year. The financial statements and related notes do not include all information and footnotes required by GAAP for annual reports. The unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto for the fiscal year ended December 27, 2020 included in our Registration Statement, which was declared effective on October 20, 2021. All intercompany balances and transactions have been eliminated in consolidation. The Company does not have any components of other comprehensive income (loss) recorded within its condensed consolidated financial statements, and therefore, does not separately present a statement of comprehensive income (loss). The Company’s chief operating decision maker (the “CODM”) is its Chief Executive Officer. The CODM reviews financial performance and allocates resources at a consolidated level on a recurring basis. The Company has aggregated its operations into one operating segment and one reportable segment. Fiscal Year We use a 52- or 53-week fiscal year ending on the Sunday prior to December 31, effective beginning with the first quarter of 2019. In a 52-week fiscal year, each quarterly period is comprised of 13 weeks. The additional week in a 53-week fiscal year is added to the fourth quarter. Fiscal 2021 and 2020 each consist of 52 weeks. The fiscal periods presented in this report are the quarter and three quarters ended September 26, 2021 and September 27, 2020, respectively. Use of Estimates The preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of sales and expenses during the period. Actual results could differ from those estimates. Reverse Common Unit Split On October 20, 2021, the members of Portillo's OpCo executed the Second Amended and Restated Limited Liability Company Agreement for Portillo's OpCo, effecting a 7.4-for-1 reverse common unit split. All applicable unit data, per unit amounts and related information in the condensed consolidated financial statements and notes thereto have been adjusted retroactively to give effect to the 7.4-for-1 reverse common unit split. Leases In April 2020, the Financial Accounting Standards Board ("FASB") issued guidance related to rent concessions resulting from the COVID-19 pandemic. This guidance allows entities an election to account for eligible concessions, regardless of their form, either by (1) applying the modification framework for these concessions in accordance with FASB Accounting Standards Codification ("ASC") Topic 840, Leases or (2) accounting for the concessions as if they were made under the enforceable rights included in the original agreement. The election applies to any lessor-provided lease concession related to the impact of the COVID-19 pandemic, provided the concession does not result in a substantial increase in the rights of the lessor or in the obligations of the lessee. During the three quarters ended September 27, 2020, the Company received non-substantial concessions from certain landlords in the form of rent deferrals and abatements. The Company has elected to account for these rent concessions as if they were made under the enforceable rights included in the original agreements. The recognition of rent concessions resulting from the COVID-19 pandemic did not have a material impact on the Company's condensed consolidated financial statements as of September 26, 2021 or September 27, 2020. Deferred Offering Costs Deferred offering costs consist of costs incurred in connection with the sale of the Company’s Class A common stock in an IPO including certain legal, accounting, and other IPO related costs. At the completion of the IPO, deferred offering costs were recorded in stockholders’ equity as reduction from the proceeds of the offering. No deferred offering costs were recorded as of December 27, 2020. As of September 26, 2021, $4.6 million of deferred offering costs had been recorded in other current assets on the Company’s condensed consolidated balance sheets. Recently Issued Accounting Standards In February 2016, the FASB issued Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) ("ASC 842"). The pronouncement requires lessees to recognize a liability for lease obligations, which represents the discounted obligation to make future minimum lease payments, and a corresponding right-of-use asset on the balance sheet. The guidance requires disclosure of key information about leasing arrangements that is intended to give financial statement users the ability to assess the amount, timing, and potential uncertainty of cash flows related to leases. The update is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company is in the process of implementing ASC 842 and expects this guidance to materially impact the Company's consolidated financial statements by significantly increasing assets and liabilities on the consolidated balance sheet in order to record the right-of-use assets and related lease liabilities. However, the Company does not expect this guidance to have a significant impact on its consolidated statements of operations or consolidated statements of cash flows. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The pronouncement provides temporary optional expedients and exceptions to the current guidance on contract modifications and hedge accounting to ease the financial reporting burden related to the expected market transition from the London Interbank Offered Rate ("LIBOR") and other interbank offered rates to alternative reference rates. The guidance was effective upon issuance and generally can be applied to applicable contract modifications through December 31, 2022. The Company is currently evaluating the impact of the transition from LIBOR to alternative reference rates but do not expect a significant impact on its consolidated financial statements. Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement,” which amends the disclosure requirements for fair value measurements by removing, modifying and adding certain disclosures. This guidance is effective for years beginning after December 15, 2020, with early adoption permitted. The adoption of ASU 2018-13 did not result in a material change to its consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, which clarifies the accounting for implementation costs in cloud computing arrangements that is a service contract. The update is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company adopted this standard effective December 28, 2020. Subsequent to the adoption of ASU 2018-15, the Company will capitalize such costs within other current assets or other assets on its condensed consolidated balance sheets. The Company will amortize the implementation costs once the system is ready for its intended use, on a straight-line basis, over the term of the related service agreements, including all reasonably certain renewals. The amortization expense related to cloud computing arrangements that are service contracts will be recorded within general and administrative expenses or other operating expenses on the Company's condensed consolidated statements of operations. The adoption of ASU 2018-15 did not result in a material change to its consolidated financial statements. The Company reviewed all other recently issued accounting pronouncements and concluded that they were either not applicable or not expected to have a significant impact to its consolidated financial statements.

REVENUE RECOGNITION

9 Months Ended

Sep. 26, 2021

Revenue from Contract with Customer [Abstract]

REVENUE RECOGNITION

Revenues from retail restaurants are presented net of discounts and recognized when food and beverage products are sold to the end customer. Sales taxes collected from customers are excluded from revenues and the obligation is included in accrued liabilities until the taxes are remitted to the appropriate taxing authorities.

The Company offers delivery services to its customers. Delivery services are fulfilled by the Company and third-party service providers. In some cases, the Company makes delivery sales through Portillos.com or the Portillo's App ("Dispatch Sales"). In other cases, the Company makes delivery sales through a non-Company owned channel, such as the delivery partner’s website or app (“Marketplace Sales”).

With respect to Dispatch Sales, delivery may be performed by the Company or through a third-party service provider. The Company generally recognizes revenue, including delivery fees, when the performance obligation is complete and the food is transferred to the customer. For these sales, the Company receives payment directly from the customer at the time of sale.

With respect to Marketplace Sales, the Company generally recognizes revenue, excluding delivery fees collected by the delivery partner, when the performance obligation is complete, and control of the food is transferred to the delivery partner. The Company receives payment subsequent to the transfer of food. The payment terms with respect to Marketplace Sales are short-term in nature and are generally paid one week in arrears.

The Company sells gift cards which do not have expiration dates. The Company records the sale of the gift card as a contract liability and recognizes revenue from gift cards when: (i) the gift card is redeemed by the customer; or (ii) in the event a gift card is not expected to be redeemed, in proportion to the pattern of rights exercised by the customer (gift card breakage). The Company has determined that 11% of gift card sales will not be redeemed and will be retained by us based on a portfolio assessment of historical data on gift card redemption patterns. Gift card breakage is recorded within revenues in the condensed consolidated statements of operations. The Company recognized gift card breakage of $0.1 million and $0.6 million for the quarter and three quarters ended September 26, 2021, respectively, and $0.1 million and $0.6 million for the quarter and three quarters ended September 27, 2020, respectively.

The Company’s only revenue related to performance obligations not yet satisfied is revenue from gift cards sold but not yet redeemed. The gift card liability included in current deferred revenue on the condensed consolidated balance sheets is as follows (in thousands):


	September 26, 2021		December 27, 2020
Gift card liability	$	3,852	$	6,216

Revenue recognized in the condensed consolidated statement of operations for the redemption of gift cards that were included in their respective liability balances at the beginning of the year is as follows (in thousands):


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Revenue recognized from gift card liability balance at the beginning of the year	$	446	$	443	$	2,923	$	2,890

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

FAIR VALUE OF FINANCIAL INSTRUMENTS

9 Months Ended

Sep. 26, 2021

Fair Value Disclosures [Abstract]

FAIR VALUE OF FINANCIAL INSTRUMENTS

The Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in an orderly transaction between market participants at the measurement date. The guidance establishes three levels of the fair value hierarchy as follows:

Level 1—Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date;

Level 2—Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and

Level 3—Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data

Assets and Liabilities Measured at Fair Value on a Recurring Basis

The carrying value of the Company's cash and cash equivalents, restricted cash, accounts receivable, accounts payable and all other current assets and liabilities approximate fair values due to the short-term nature of these financial instruments.

Other assets consist of a deferred compensation plan with related assets held in a rabbi trust.

Deferred Compensation Plan - The Company maintains a rabbi trust to fund obligations under a deferred compensation plan. Amounts in the rabbi trust are invested in mutual funds, which are designated as trading securities carried at fair value. The fair value measurement of these trading securities is considered Level 1 of the fair value hierarchy as they are measured using quoted market prices. As of September 26, 2021 and December 27, 2020, the fair value of the mutual fund investments and deferred compensation obligations were as follows:


	September 26, 2021						December 27, 2020
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets - Investments designated for deferred compensation plan
Cash/money accounts	$	1,447	$	—	$	—	$	481	$	—	$	—
Mutual Funds	2,776		—		—		3,643		—		—
Total assets	$	4,223	$	—	$	—	$	4,124	$	—	$	—

The mutual fund investments and deferred compensation obligations are included in other assets, accrued expenses and other long-term liabilities in the condensed consolidated balance sheets. Changes in the fair value of securities held in the rabbi trust are recognized as trading gains and losses and included in other income in the condensed consolidated statements of operations and offsetting increases or decreases in the deferred compensation obligation are recorded in other long-term liabilities in the condensed consolidated balance sheets.

Refer to "Note 9 – Debt" for additional information relating to the fair value of the Company's outstanding debt instruments.

Assets and Liabilities Measured at Fair Value on a Non-Recurring BasisAssets and liabilities that are measured at fair value on a non-recurring basis include property and equipment, net, equity-method investment, goodwill and indefinite-lived intangible assets. These assets are measured at fair value whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. There were no impairment charges recognized during the quarter and three quarters ended September 26, 2021 and September 27, 2020.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

INVENTORIES

9 Months Ended

Sep. 26, 2021

Inventory Disclosure [Abstract]

INVENTORIES

INVENTORIESInventories consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
Raw materials	$	2,705	$	3,999
Work in progress	99		112
Finished goods	1,168		715
Consigned inventory	427		249
	$	4,399	$	5,075

PROPERTY & EQUIPMENT, NET

9 Months Ended

Sep. 26, 2021

Property, Plant and Equipment [Abstract]

PROPERTY & EQUIPMENT, NET

Property and equipment, net consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
Land improvements	$	15,347	$	15,039
Furniture, fixtures, and equipment	112,930		105,059
Leasehold improvements	130,093		115,695
Transportation equipment	2,203		2,285
Construction-in-progress	12,206		10,711
	272,779		248,789
Less accumulated depreciation	(86,158)		(74,020)
	$	186,621	$	174,769

Depreciation expense was $4.3 million and $12.6 million for the quarter and three quarters ended September 26, 2021, respectively, and $3.9 million and $11.8 million for the quarter and three quarters ended September 27, 2020, respectively, and is included in depreciation and amortization in the condensed consolidated statements of operations.

GOODWILL & INTANGIBLE ASSETS

9 Months Ended

Sep. 26, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

GOODWILL & INTANGIBLE ASSETS

GOODWILL & INTANGIBLE ASSETSThe Company has one reporting unit for goodwill which is evaluated for impairment annually in the fourth quarter of each fiscal year. The Company used the income approach and market approach to test goodwill. Under the income approach, fair value is based on the present value of estimated future cash flows. The market approach utilized both the price-earnings multiples of comparable public companies, as well as transactional data from similar companies that were recently sold. Adjustments are then made for any dissimilarities, to appropriately compare and correlate the market transactions used in this method. In estimating the fair value of the Company under the market approach, the most significant assumptions include the selection of the guideline public companies used in the analysis and the selection of EBITDA multiples. The most significant assumptions utilized in the fair value estimate of the income approach include projected annual revenue, earnings before interest, taxes, depreciation and amortization ("EBITDA"), capital expenditures and the discount rate. Growth assumptions were primarily based on a combination of historical performance, expected comparable store sales growth, the number of new restaurant additions, and performance of new restaurants.

For indefinite-lived intangibles, the relief-from-royalty method estimates the fair value of an intangible asset based on what a third party would pay for the right to use that asset. The most significant assumptions utilized in the relief-from-royalty method are projected revenues and the royalty rate.

No impairment charges were recognized for goodwill or indefinite-lived intangible assets for the quarter and three quarters ended September 26, 2021 and September 27, 2020.

Intangibles, net consisted of the following (in thousands):


	As of September 26, 2021

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(20,705)		35,412
Covenants not-to-compete	40,799		(40,799)		—
Favorable rental contracts	2,991		(1,787)		1,204
	$	323,832	$	(63,291)	$	260,541

	As of December 27, 2020

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(18,538)		37,579
Covenants not-to-compete	40,799		(37,515)		3,284
Favorable rental contracts	2,991		(1,599)		1,392
	$	323,832	$	(57,652)	$	266,180

Amortization expense was $1.2 million and $5.6 million for the quarter and three quarters ended September 26, 2021, respectively, and $2.2 million and $6.6 million for the quarter and three quarters ended September 27, 2020, respectively, and is included in depreciation and amortization in the condensed consolidated statements of operations.

The estimated aggregate amortization expense for the intangibles for the remainder of this year and the succeeding five years and thereafter are $0.8 million, $3.1 million, $3.1 million, $3.0 million, $3.0 million, $2.9 million and $20.7 million, respectively.

EQUITY METHOD INVESTMENT

9 Months Ended

Sep. 26, 2021

Equity Method Investments and Joint Ventures [Abstract]

EQUITY METHOD INVESTMENT

The Company has a 50% interest in C&O Chicago, LLC ("C&O"). The Company accounts for the investment and financial results in the condensed consolidated financial statements under the equity method of accounting as the Company has significant influence but does not have control. The investment is adjusted to reflect the Company’s share of C&O’s earnings and losses to date and any distributions received.

A summary of financial information for C&O is as follows (in thousands):


	September 26, 2021		December 27, 2020
Assets:
Current assets	$	2,058	$	1,349
Property, plant, and equipment, net of accumulated depreciation $5,921 and $5,838 in 2021 and 2020, respectively	821		837
Total assets	2,879		2,186

Liabilities:
Current liabilities	709		681
Non-current liabilities
Deferred rent	1,206		1,193
Total liabilities	1,915		1,874

Members’ equity	964		312
Total liabilities and members' equity	$	2,879	$	2,186


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Results from operations:
Sales	$	3,608	$	2,815	$	9,205	$	8,480
Net income	585		242		1,303		707

DEBT

9 Months Ended

Sep. 26, 2021

Debt Disclosure [Abstract]

DEBT

Debt consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
First Lien Term B-3 Loans	$	326,583	$	329,076
Revolving Loans	—		—
Second Lien Term B-3 Loans	155,000		155,000
Unamortized discount and debt issuance costs	(11,495)		(14,372)
Total debt, net	470,088		469,704
Less: current portion	(3,324)		(3,324)
Long-term debt, net	$	466,764	$	466,380

First Lien

PHD Intermediate LLC (“Holdings”), Portillo’s Holdings LLC (the “Borrower”) and certain of its subsidiaries entered into the First Lien Credit Agreement ("First Lien Credit Agreement"), dated as of August 1, 2014 and as amended October 25, 2016, May 18, 2018 and December 6, 2019, with UBS AG, Stamford Branch, as the administrative agent and collateral agent, and other lenders from time to time party thereto (the “First Lien Lenders”). The First Lien Lenders extended credit in the form of (i) first lien initial term loans in an initial aggregate principal amount of $335.0 million and (ii) a revolving credit facility in an original principal amount equal to $30.0 million, including a letter of credit sub-facility with a $7.5 million sublimit (the “Revolving Facility” and the loans thereunder, the “Revolving Loans”).

On December 6, 2019, the Borrower entered a third amendment to the First Lien Credit Agreement (the “Third Amendment to First Lien Credit Agreement”) whereby the aggregate principal amount of the term loans as of the effective date of the Third Amendment to First Lien Credit Agreement was $332.4 million (the “First Lien Term B-3 Loans”), and the Revolving Facility was increased by $50 million. The maturity date with respect to the First Lien Term B-3 Loans was extended to September 6, 2024 and the maturity date with respect to the Revolving Loans date was extended to June 6, 2024.

In connection with the Third Amendment to First Lien Credit Agreement, the interest rates spread for the First Lien Term B-3 Loans increased by 100 basis points to 5.50% for the adjusted London interbank offered rate ("Eurocurrency Rate") loans. As of September 26, 2021, the interest rate on the Term Loans was 6.50%. As of September 26, 2021 and September 27, 2020, the effective interest rate on the Term Loans was 7.80% and 7.52%, respectively. Beginning with December 31, 2019, the Company is required to pay on the last business day of each calendar quarter, March 31, June 30, September 30, and December 31, an aggregate principal amount of $0.8 million.

As of September 26, 2021 and December 27, 2020, the Company had $0.0 million in borrowings under the Revolver outstanding, respectively. As of September 26, 2021 and September 27, 2020, the interest rate on the Revolver was 3.25% and 3.50%, respectively, subject to change based on a consolidated first lien net leverage ratio as defined in the First Lien Credit Agreement. As of September 26, 2021 and September 27, 2020, the commitment fees, pursuant to the First Lien, to maintain the Revolver were 0.250% and 0.375%, respectively. Also pursuant to the First Lien Credit Agreement, as of September 26, 2021 and September 27, 2020, letter of credit fronting fees were 0.125%. Commitment fees and letter of credit fronting fees are recorded as interest expense in the condensed consolidated statements of operations.

The Company had $5.3 million and $5.8 million of letters of credit issued against the Revolving Facility as of September 26, 2021 and December 27, 2020, respectively. As of September 26, 2021, the Company had $44.7 million of availability under the Revolving Facility.

Second Lien

Holdings, the Borrower and certain of its subsidiaries entered into the Second Lien Credit Agreement (the “Second Lien Credit Agreement”) dated as of August 1, 2014 and as amended on October 25, 2016 and December 6, 2019 with UBS AG, Stamford Branch, as administrative agent and collateral agent, and other lenders from time to time party thereto (the “Second Lien Lenders”). The Second Lien Lenders extended

credit in the form of initial second lien term loans in an initial aggregate principal amount of $80.0 million.

On December 6, 2019, the Borrower entered into second amendment to the Second Lien Credit Agreement (the “Second Amendment to Second Lien Credit Agreement”) whereby the aggregate principal amount of the term loans as of the effective date of the Second Amendment to the Second Lien Credit Agreement was $155.0 million (the “Second Lien Term B-3 Loans”). The maturity date of the Second Lien Term B-3 Loans was extended to December 6, 2024 (the “Second Lien Maturity Date”). In addition to the increased principal amount, the interest rates spread for the Second Lien Term B-3 Loans increased by 150 basis points to 9.50% for Eurocurrency Rate loans. The Borrower determined interest on the Second Lien at the Eurocurrency Rate, plus 9.50%. As of September 26, 2021, the interest rate on the Term Loans was 10.75%. As of September 26, 2021 and September 27, 2020, the effective interest rate on the Second Lien was 12.22% and 11.90%, respectively. No principal payments are required. The aggregate principal is due on the Second Lien Maturity Date.

In connection with the IPO, the Company received aggregate net proceeds of approximately $429.9 million after deducting underwriting discounts and commissions and offering expenses. Net proceeds of $158.1 million were used to repay the Second Lien Term B-3 Loans (including prepayment penalties) in full.

Discount and Debt Issuance Costs

In connection with entering into the Third Amendment to First Lien Credit Agreement and the Second Amendment to Second Lien Credit Agreement, in each case, dated as of December 6, 2019, the Borrower paid debt issuance costs of $14.5 million, of which $13.3 million were capitalized and are being amortized over the term of the related debt agreements, and $1.2 million were expensed as incurred.

The Company amortized $0.6 million of deferred financing costs, respectively, during each of the quarters ended September 26, 2021 and September 27, 2020, and $1.7 million of deferred financing costs, respectively, during each of the three quarters ended September 26, 2021 and September 27, 2020, which is included in interest expense in the condensed consolidated statements of operations. In addition, the Company also amortized $0.4 million in original issue discount related to the long-term debt, which is included in interest expense in the condensed consolidated statements of operations in each of the quarters ended September 26, 2021 and September 27, 2020, respectively, and $1.2 million in original issue discount related to long-term debt in each of the three quarters ended September 26, 2021 and September 27, 2020, which is included in interest expense in the condensed consolidated statements of operations.

Total interest costs incurred were $10.7 million and $10.8 million for the quarters ended September 26, 2021 and September 27, 2020, respectively and $32.1 million and $34.3 million for the three quarters ended September 26, 2021 and September 27, 2020.

As of September 26, 2021 and December 27, 2020, the fair value of long-term debt approximates the carrying value as it is variable rate debt. The fair value measurement of this debt is considered Level 2 of the fair value hierarchy as inputs to interest are observable, unadjusted quoted prices in active markets for similar assets or liabilities.

Borrowings under the First Lien Credit Agreement and Second Lien Credit Agreement are guaranteed by Holdings, the Borrower and certain of the Borrower’s subsidiaries, and Holdings, the Borrower and certain of the Borrower’s subsidiaries have pledged substantially all tangible and intangible assets as collateral, subject to certain exclusions and exceptions.

The Borrower is subject to certain financial and reporting covenants pursuant to the terms of the First Lien Credit Agreement and Second Lien Credit Agreement. These covenants are customary for these types of debt agreements. As of September 26, 2021, the Company was in compliance with all covenants.

- Definition

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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-Paragraph 1B
-Subparagraph (h)
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(c))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1C
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-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611

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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611

+ Details

REDEEMABLE PREFERRED UNITS	9 Months Ended
REDEEMABLE PREFERRED UNITS	Sep. 26, 2021
Temporary Equity [Abstract]
REDEEMABLE PREFERRED UNITS	REDEEMABLE PREFERRED UNITS Pursuant to a unit purchase agreement, dated August 1, 2014, between the Company and Broad Street Principal Investments (the “Preferred Investor”), Portillo's OpCo issued 100,000 preferred units in exchange for a capital contribution of $97.7 million, net of discounts and fees as agreed between the parties. The Preferred Units have all the rights, privileges, and obligations as provided for in the Amended and Restated Limited Liability Company Agreement of the Company (the “LLC Agreement”), which include redemption rights and the amounts payable upon liquidation, but exclude dividend and conversion rights. Preferred Yield Pursuant to the LLC Agreement, each Preferred Unit accrues on a daily basis the following applicable preferred rate, subject to certain triggering events as defined in the LLC Agreement that would result in an additional 2% to the prevailing rate below: •11% per year until the eighth anniversary of the closing date •12% per year from the eighth to the tenth anniversary of the closing date •13% per year thereafter The rate accrues daily and compounds semiannually on June 30 and December 31 of each year on the sum of the preferred unreturned capital contributions and the unpaid Preferred Yield outstanding that has compounded for all prior periods. Call Rights The Company can, on or after the first anniversary of the closing date, choose to redeem the Preferred Units in whole or in part, by giving proper written notice as required in the LLC Agreement. The redemption price is a premium percentage, as noted below, applied to the sum of the unreturned capital contributions for the Preferred Units and the unpaid Preferred Yield (together, the “Preferred Liquidation Amount”). As of September 26, 2021, the percentage of Preferred Liquidation Amount is 101%. Put Rights The Preferred Units holder can also require the Company to redeem the Preferred Units, in whole or in part, by delivering proper written notice (i) immediately prior to or simultaneously with a sale of the Company or (ii) at any time from and after the twelfth anniversary of the closing date. The redemption price is specified in the LLC Agreement. As of September 26, 2021 and December 27, 2020, the Company had recorded $217.5 million and $200.6 million respectively, as Redeemable Preferred Units. These transactions were recorded in accordance with FASB ASC 480 Distinguishing Between Liabilities and Equity. As a result of the probability of the redemption by holder feature, the Preferred Units are classified outside of permanent equity within the condensed consolidated balance sheets. In connection with the IPO, the Company received aggregate net proceeds of approximately $429.9 million after deducting underwriting discounts and commissions and offering expenses. Net proceeds of $221.7 million were used to repay the redeemable preferred units in full including the Preferred Liquidation Amount.

COMMON UNITS AND UNIT-BASED COMPENSATION	9 Months Ended
COMMON UNITS AND UNIT-BASED COMPENSATION	Sep. 26, 2021
Share-based Payment Arrangement [Abstract]
COMMON UNITS AND UNIT-BASED COMPENSATION	COMMON UNITS AND UNIT-BASED COMPENSATION Common Units As of September 26, 2021 and December 27, 2020, the Company had 51,210,222 and 51,192,434 Class A Common Units outstanding, respectively. The increase of 131,578 Class A Common Units was primarily attributable to the issuance of common units to a member of the Company’s Board during the three quarters ended September 26, 2021.The Company has 7,477,256 options authorized to purchase Class A Common Units as designated by the Company’s 2014 Equity Incentive Plan, as amended (the "2014 Plan"). 2014 Equity Incentive Plan The Company has granted options to acquire units under its 2014 Plan. The 2014 Plan permits the granting of awards to employees, officers, directors and consultants of the Company and affiliates in the form of options, unit appreciation rights, Restricted Class A Units, Unrestricted Class A Units, Performance Awards and awards convertible into or otherwise based on Class A Units. The 2014 Plan gives broad powers to the Company’s Board to administer and interpret the 2014 Plan, including the authority to select the individuals to be granted awards and rights to prescribe the particular form and conditions of each award to be granted. As of September 26, 2021, the Company had 40,558 options available to be issued under the 2014 Plan. Under the 2014 Plan, the number of common units and exercise price of each option were determined prior to the IPO by the board of managers (the “Board of Managers”), or a committee designated by the Board of Managers. The awards granted are generally exercisable within a 10-year period from the date of grant. As of September 26, 2021, the Company has issued options with time vesting, and other options with time and performance vesting. The Company’s performance condition restricts certain option holders’ ability to exercise vested options until a liquidity event and payback criteria to the Buyer are both met. Because these events, conditions or criteria were not considered probable as of September 26, 2021, no compensation expense related to these options to acquire units was recognized. For options to acquire units granted without performance conditions, the Company records compensation expense over the vesting period based on the grant-date fair value of the option, determined using the Black-Scholes option pricing valuation model. Options issued and outstanding expire on various dates through the year 2031. The exercise price on all options outstanding as of September 26, 2021, range from $3.25 to $5.77, and the options vest over a range of immediately to five-year periods. No additional options will be issued under the 2014 Plan. See "Note 15 – Subsequent Events" for a description of the treatment of the options to acquire units in connection with the IPO. Unit-Based Compensation Expense In accordance with FASB ASC Topic 718, Compensation-Stock Compensation, stock-based compensation is measured at the grant date, based on the calculated fair value of the award, and is recognized as an expense over the requisite service period (generally the vesting period of the grant). The Company recognized $0.2 million and $0.4 million of stock-based compensation expense for the quarter and three quarters ended September 26, 2021 and $0.2 million and $0.6 million for the quarter and three quarters ended September 27, 2020, respectively, with a corresponding increase to additional paid-in-capital. Unit-based compensation expense is calculated based on awards ultimately expected to vest and is reduced for estimated forfeitures. Forfeitures are revised, if necessary, in subsequent periods if actual forfeitures differ from those estimates and an adjustment to unit-based compensation expense will be recognized at that time. Unit-based compensation expense is included in general and administrative expenses on the condensed consolidated statements of operations.

CONTINGENCIES	9 Months Ended
CONTINGENCIES	Sep. 26, 2021
Commitments and Contingencies Disclosure [Abstract]
CONTINGENCIES	CONTINGENCIES The Company is party to legal proceedings and potential claims arising in the normal conduct of business, including claims related to employment matters, contractual disputes, customer injuries, and property damage. Although the ultimate outcome of these claims and lawsuits cannot be predicted with certainty, management believes that the resulting liability, if any, will not have a material effect on the Company’s consolidated financial statements. The Company is subject to unclaimed property laws by states in the ordinary course of business. These laws generally require entities to report and remit abandoned and unclaimed property to the state which includes unclaimed wages, gift card funds, vendor payments, and customer refunds. Failure to timely report and remit the property can result in assessments that could include interest and penalties, in addition to the payment of the escheat liability. The Company routinely remits payments to states in compliance with applicable unclaimed property laws. As of September 26, 2021 and December 27, 2020, the Company recorded a $0.0 million and $0.9 million loss contingency related to the probable loss that may arise from an obligation to report and deliver unclaimed gift card funds. This loss contingency was resolved during the quarter ended September 26, 2021 for $0.8 million.

RELATED PARTY TRANSACTIONS	9 Months Ended
RELATED PARTY TRANSACTIONS	Sep. 26, 2021
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS As of September 26, 2021 and December 27, 2020, the related parties’ receivables consisted of a receivable balance due from C&O of $0.3 million and $0.2 million, respectively, which is included in accounts receivable in the condensed consolidated balance sheets. The Company previously issued 195,933 common units to the CEO and President for a unit subscription receivable of $1.0 million. As of September 26, 2021 and December 27, 2020, the Company had $0.0 million and $0.5 million recorded as subscription receivable, respectively. On August 13, 2021, the remaining stock subscription receivable of $0.2 million was fully repaid. Also, Noah Glass, a member of the Company's Board, is the founder and CEO of Mobo Systems, Inc. (also known as "Olo"), a platform the Company uses in connection with our mobile ordering application and delivery. The Company incurred $0.3 million and $0.7 million in net Olo-related costs for the quarter and three quarters ended September 26, 2021. Of these expenses, $0.2 million and $0.4 million, respectively, were included in cost of goods sold and $0.1 million and $0.3 million, respectively, were included in other operating expenses in the condensed consolidated statements of operations. The Company incurred $0.3 million and $0.9 million in net Olo-related costs for the quarter and three quarters ended September 27, 2020. Of these expenses, $0.2 million and $0.6 million, respectively, were included in cost of goods sold and $0.1 million and $0.3 million, respectively, were included in other operating expenses in the condensed consolidated statements of operations. As of September 26, 2021 and December 27, 2020, $0.0 million and $0.2 million was payable to Olo and was included in accounts payable in the consolidated balance sheets. Additionally, the Company leases 23 real properties from entities owned and controlled by Richard Portillo. Mr. Portillo was the former President, CEO, and Owner of the Company, as comprised at the date of the merger transaction in August 2014 through which the Company was acquired by funds affiliated or managed by Berkshire Partners LLC. The Company made $2.0 million and $1.9 million in rental payments related to the aforementioned 23 locations, during each of the quarters ended September 26, 2021 and September 27, 2020, respectively, and $5.9 million and $5.6 million in rental payments, during each of the three quarters ended September 26, 2021 and September 27, 2020. Beginning in 2014 through July 31, 2021, Mr. Portillo served as a consultant, under an Agreement with Portillo's Holdings, LLC (the "Consulting Agreement"). Under the terms of the Consulting Agreement, $2.0 million was paid annually for various consulting services, which was included in general and administrative expenses in the condensed statements of operations. The Consulting Agreement terminated on July 31, 2021 and has not been renewed.

EARNINGS (LOSS) PER UNIT

9 Months Ended

Sep. 26, 2021

Earnings Per Share [Abstract]

EARNINGS (LOSS) PER UNIT

Basic earnings (loss) per unit is computed by dividing net income (loss) available to common unitholders by the weighted-average number of common units outstanding during the year.

Net income (loss) applicable to common unitholders is calculated after deducting any redeemable preferred unit accretion.

Diluted earnings (loss) per unit is computed by dividing net income available to common unit holders by the weighted-average number of common units outstanding inclusive of the incentive common units, using the treasury stock method, if dilutive.

For the quarter and three quarters ended September 26, 2021 and September 27, 2020, the potential dilutive units related to the incentive common units were not included in the computation of diluted net loss per unit as the effect of including these units in the calculation would have been anti-dilutive.

The computations of basic and diluted earnings (loss) per unit for the quarter and three quarters ended September 26, 2021 and September 27, 2020 are as follows (in thousands, except per share amounts):


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Net income	$	6,531	$	8,104	$	20,404	$	7,371
Less: Redeemable Preferred Units Accretion	(5,886)		(5,282)		(16,978)		(15,240)
Net income (loss) attributable to common unit holders	$	645	$	2,822	$	3,426	$	(7,869)

Units:
Weighted-average number of common units outstanding-basic	51,210,222		51,192,285		51,201,100		51,187,878
Dilutive unit awards	371,463		217,717		367,934		—
Weighted-average number of common units outstanding-diluted	51,581,685		51,410,002		51,569,034		51,187,878

Basic net income (loss) per unit	$	0.01	$	0.06	$	0.07	$	(0.15)
Diluted net income (loss) per unit	$	0.01	$	0.05	$	0.07	$	(0.15)

The following units were excluded from the calculation of diluted earnings per share because they would be anti-dilutive:


	Quarter Ended		Three Quarters Ended
	September 26, 2021	September 27, 2020	September 26, 2021	September 27, 2020
Units subject to performance conditions	318,514	57,729	318,704	57,729
Units that were antidilutive	—	—	—	216,926
Total units excluded from diluted income (loss) per unit	318,514	57,729	318,704	274,655

SUBSEQUENT EVENTS	9 Months Ended
SUBSEQUENT EVENTS	Sep. 26, 2021
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS The Company's registration statement on Form S-1, as amended (Registration No. 333-259810) (the "Registration Statement"), related to its IPO was declared effective October 20, 2021, and the Company's Class A common stock began trading on the Nasdaq Global Select Market on October 21, 2021. On October 25, 2021, the Company completed its IPO of 23,310,810 shares of the Company's Class A common stock (including 3,040,540 shares sold to the underwriters pursuant to their overallotment option), $0.01 par value per share, at an offering price of $20.00 per share. The Company received aggregate net proceeds of approximately $429.9 million after deducting underwriting discounts and commissions of $29.1 million and other offering expenses of approximately $7.2 million. In connection with the IPO, we completed the following: •We amended and restated the limited liability company agreement of Portillo’s OpCo to, among other things, convert all outstanding equity interests (except for those redeemable preferred units which were redeemed in connection with this offering) into LLC Units. •We became the sole managing member of Portillo's OpCo. Because we manage and operate the business and control the strategic decisions and day-to-day operations of Portillo’s OpCo and because we also have a substantial financial interest in Portillo’s OpCo, we will consolidate the financial results of Portillo’s OpCo, and a portion of our net income will be allocated to non-controlling interests to reflect the entitlement of the pre-IPO LLC members who retained their equity ownership in Portillo's OpCo. In addition, because Portillo’s OpCo will be under the common control of the pre-IPO LLC members before and after the reorganization, we will initially measure the assets and liabilities of Portillo’s OpCo at their carrying amounts as of the date of the completion of the reorganization. •We amended and restated our certificate of incorporation to authorize the issuance of two classes of common stock: Class A common stock and Class B common stock. Each share of Class A common stock and Class B common stock will entitle its holder to one vote per share on all matters submitted to a vote of our stockholders. The Class B common stock is not entitled to economic interests in Portillo’s Inc. The Company received net proceeds from the offering of approximately $429.9 million (after deducting underwriting fees and commissions and offering expenses). The net proceeds and cash on hand were used as follows: •to repay the redeemable preferred units in full (including the redemption premium) of $221.7 million; •to repay all of the borrowings outstanding under the Second Lien Credit Agreement (including any prepayment penalties) of $158.1 million; and •to purchase LLC Units or shares of Class A common stock from certain pre-IPO LLC members of $57.0 million. In connection with the IPO, the Company entered into a Tax Receivable Agreement (the “Tax Receivable Agreement”) with certain pre-IPO LLC Members, pursuant to which Portillo's Inc. is obligated to pay 85% of the amount of applicable cash tax savings, if any, in U.S. federal, state, and local income tax or franchise tax that Portillo's Inc. actually realizes as a result of (a) the increases in tax basis attributable to exchanges of LLC Units by pre-IPO LLC Members and (b) tax benefits related to imputed interest deemed to be paid by Portillo's Inc. as a result of the Tax Receivable Agreement. We will retain the benefit of the remaining 15% of these tax savings. In connection with the IPO, each option under the 2014 Equity Incentive Plan (the "2014 Plan") that was outstanding, whether vested or unvested, was substituted for an option to purchase a number of shares of Class A common stock under the Company's 2021 Equity Incentive Plan (the "2021 Plan") adopted in connection with the IPO, and the option holders received a cash payment in respect of their options (whether vested or unvested) in an aggregate amount of approximately $6.3 million, which we expect to make in the fourth quarter of fiscal 2021. In addition, as a result of the waiver and the resultant modification in the terms of certain performance-vesting awards, we will record compensation expense based on the fair value of the modified awards in the fourth quarter of fiscal 2021. We would expect to recognize a cash compensation expense of approximately $1.3 million and a non-cash compensation expense of approximately $23.3 million, each in the fourth quarter of fiscal 2021, as well as, an additional non-cash compensation expense of approximately $12.7 million ratably over the next 4.5 years. In connection with the IPO, the Company granted options to purchase shares of Class A common stock under the 2021 Plan. The 2021 Plan permits the granting of awards to any employee, officer, non-employee director, consultant or other personal service provider of the Company in the form of stock options, stock appreciation rights, restricted stock awards, restricted stock units and stock-based awards. All awards granted to participants under the 2021 Plan generally will be represented by an award agreement. 7,148,049 shares of Class A common stock are available for awards under the 2021 Plan (excluding options previously awarded under the 2014 Plan that were assumed by the 2021 Plan). The 2021 Plan gives broad powers to the Company’s Board of Directors (the "Board") to administer and interpret the 2021 Plan, including the authority to select the individuals to be granted awards and rights to prescribe the particular form and conditions of each award to be granted. The Company is a holding company and its sole material asset is an ownership interest in Portillo’s OpCo. SUBSEQUENT EVENTS The Company opened one new restaurant subsequent to September 26, 2021 for a total of 67 restaurants, excluding a restaurant owned by C&O, of which Portillo's owns 50% of the equity. On October 25, 2021, Portillo's Inc. completed the IPO of its Class A common stock. Portillo's Inc. issued 23,310,810 shares, including 3,040,540 shares sold to the underwriters pursuant to their overallotment option. Portillo's Inc. received net proceeds from the offering of approximately $429.9 million (after deducting $29.1 million of underwriting fees and commissions and approximately $7.2 million of offering expenses). The net proceeds and cash on hand were used to as follows: •to repay the redeemable preferred units in full (including the redemption premium) of $221.7 million; •to repay all of the borrowings outstanding under the Second Lien Credit Agreement (including prepayment penalties) of $158.1 million; and •to purchase LLC Units or shares of Class A common stock from certain pre-IPO LLC members of $57.0 million. On October 20, 2021, the members of Portillo's OpCo executed the Second Amended and Restated Limited Liability Company Agreement for Portillo's OpCo, effecting a 7.4-for-1 reverse common unit split. In connection with the IPO, Portillo's Inc. entered into a Tax Receivable Agreement (the “Tax Receivable Agreement”) with certain pre-IPO LLC Members, pursuant to which Portillo's Inc. is obligated to pay 85% of the amount of applicable cash tax savings, if any, in U.S. federal, state, and local income tax or franchise tax that Portillo's Inc. actually realizes as a result of (a) the increases in tax basis attributable to exchanges of LLC Units by pre-IPO LLC Members and (b) tax benefits related to imputed interest deemed to be paid by Portillo's Inc. as a result of the Tax Receivable Agreement. We will retain the benefit of the remaining 15% of these tax savings. In connection with the IPO, each option under the 2014 Plan that was outstanding, whether vested or unvested, was substituted for an option to purchase a number of shares of Class A common stock under the 2021 Plan, and the option holders received a cash payment in respect of their options (whether vested or unvested) in an aggregate amount of approximately $6.3 million, which Portillo's Inc. expects to make in the fourth quarter of fiscal 2021. In addition, as a result of the waiver and the resultant modification in the terms of certain performance-vesting awards, Portillo's Inc. will record compensation expense based on the fair value of the modified awards in the fourth quarter of fiscal 2021. We would expect to recognize a cash compensation expense of approximately $1.3 million and a non-cash compensation expense of approximately $23.3 million, each in the fourth quarter of fiscal 2021, as well as an additional non-cash compensation expense of approximately $12.7 million ratably over the next 4.5 years. In connection with the IPO, Portillo's Inc. granted options to purchase shares of Class A common stock under its 2021 Plan. The 2021 Plan permits the granting of awards to any employee, officer, non-employee director, consultant or other personal service provider of the Company in the form of stock options, stock appreciation rights, restricted stock awards, restricted stock units and stock-based awards. All awards granted to participants under the 2021 Plan generally will be represented by an award agreement. 7,148,049 shares of Class A common stock are available for awards under the 2021 Plan (excluding options previously awarded under the 2014 Plan that were assumed by the 2021 Plan). The 2021 Plan gives broad powers to the Board to administer and interpret the 2021 Plan, including the authority to select the individuals to be granted awards and rights to prescribe the particular form and conditions of each award to be granted. As of October 25, 2021, following the issuance of the stock sold in the IPO, Portillo's Inc. had a total of 35,807,171 shares of Class A common stock issued and outstanding, 35,673,321 shares of Class B common stock issued and outstanding and no preferred shares issued and outstanding.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Sep. 26, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("GAAP") for interim financial information. The Company has prepared the accompanying unaudited condensed consolidated financial statements in accordance with GAAP for interim financial statements and pursuant to the rules and regulations of the Securities and Exchange Commission (the "SEC"). In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments consisting of normal recurring adjustments necessary for a fair presentation of our financial position and results of operations. Interim results of operations are not necessarily indicative of the results that may be achieved for the full year. The financial statements and related notes do not include all information and footnotes required by GAAP for annual reports. The unaudited condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes thereto for the fiscal year ended December 27, 2020 included in our Registration Statement, which was declared effective on October 20, 2021. All intercompany balances and transactions have been eliminated in consolidation. The Company does not have any components of other comprehensive income (loss) recorded within its condensed consolidated financial statements, and therefore, does not separately present a statement of comprehensive income (loss). The Company’s chief operating decision maker (the “CODM”) is its Chief Executive Officer. The CODM reviews financial performance and allocates resources at a consolidated level on a recurring basis. The Company has aggregated its operations into one operating segment and one reportable segment.
Fiscal Year	Fiscal Year We use a 52- or 53-week fiscal year ending on the Sunday prior to December 31, effective beginning with the first quarter of 2019. In a 52-week fiscal year, each quarterly period is comprised of 13 weeks. The additional week in a 53-week fiscal year is added to the fourth quarter. Fiscal 2021 and 2020 each consist of 52 weeks. The fiscal periods presented in this report are the quarter and three quarters ended September 26, 2021 and September 27, 2020, respectively.
Use of Estimates	Use of EstimatesThe preparation of these condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of sales and expenses during the period. Actual results could differ from those estimates.
Leases	Leases In April 2020, the Financial Accounting Standards Board ("FASB") issued guidance related to rent concessions resulting from the COVID-19 pandemic. This guidance allows entities an election to account for eligible concessions, regardless of their form, either by (1) applying the modification framework for these concessions in accordance with FASB Accounting Standards Codification ("ASC") Topic 840, Leases or (2) accounting for the concessions as if they were made under the enforceable rights included in the original agreement. The election applies to any lessor-provided lease concession related to the impact of the COVID-19 pandemic, provided the concession does not result in a substantial increase in the rights of the lessor or in the obligations of the lessee. During the three quarters ended September 27, 2020, the Company received non-substantial concessions from certain landlords in the form of rent deferrals and abatements. The Company has elected to account for these rent concessions as if they were made under the enforceable rights included in the original agreements. The recognition of rent concessions resulting from the COVID-19 pandemic did not have a material impact on the Company's condensed consolidated financial statements as of September 26, 2021 or September 27, 2020.
Recently Issued and Adopted Accounting Standards	Recently Issued Accounting Standards In February 2016, the FASB issued Accounting Standards Update ("ASU") No. 2016-02, Leases (Topic 842) ("ASC 842"). The pronouncement requires lessees to recognize a liability for lease obligations, which represents the discounted obligation to make future minimum lease payments, and a corresponding right-of-use asset on the balance sheet. The guidance requires disclosure of key information about leasing arrangements that is intended to give financial statement users the ability to assess the amount, timing, and potential uncertainty of cash flows related to leases. The update is effective for fiscal years beginning after December 15, 2021, with early adoption permitted. The Company is in the process of implementing ASC 842 and expects this guidance to materially impact the Company's consolidated financial statements by significantly increasing assets and liabilities on the consolidated balance sheet in order to record the right-of-use assets and related lease liabilities. However, the Company does not expect this guidance to have a significant impact on its consolidated statements of operations or consolidated statements of cash flows. In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The pronouncement provides temporary optional expedients and exceptions to the current guidance on contract modifications and hedge accounting to ease the financial reporting burden related to the expected market transition from the London Interbank Offered Rate ("LIBOR") and other interbank offered rates to alternative reference rates. The guidance was effective upon issuance and generally can be applied to applicable contract modifications through December 31, 2022. The Company is currently evaluating the impact of the transition from LIBOR to alternative reference rates but do not expect a significant impact on its consolidated financial statements. Recently Adopted Accounting Standards In August 2018, the FASB issued ASU 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework—Changes to the Disclosure Requirements for Fair Value Measurement,” which amends the disclosure requirements for fair value measurements by removing, modifying and adding certain disclosures. This guidance is effective for years beginning after December 15, 2020, with early adoption permitted. The adoption of ASU 2018-13 did not result in a material change to its consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles-Goodwill and Other-Internal-Use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract, which clarifies the accounting for implementation costs in cloud computing arrangements that is a service contract. The update is effective for fiscal years beginning after December 15, 2020, with early adoption permitted. The Company adopted this standard effective December 28, 2020. Subsequent to the adoption of ASU 2018-15, the Company will capitalize such costs within other current assets or other assets on its condensed consolidated balance sheets. The Company will amortize the implementation costs once the system is ready for its intended use, on a straight-line basis, over the term of the related service agreements, including all reasonably certain renewals. The amortization expense related to cloud computing arrangements that are service contracts will be recorded within general and administrative expenses or other operating expenses on the Company's condensed consolidated statements of operations. The adoption of ASU 2018-15 did not result in a material change to its consolidated financial statements. The Company reviewed all other recently issued accounting pronouncements and concluded that they were either not applicable or not expected to have a significant impact to its consolidated financial statements.

REVENUE RECOGNITION (Tables)

9 Months Ended

Sep. 26, 2021

Revenue from Contract with Customer [Abstract]

Summary of Gift Card Liability

The gift card liability included in current deferred revenue on the condensed consolidated balance sheets is as follows (in thousands):


	September 26, 2021		December 27, 2020
Gift card liability	$	3,852	$	6,216


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Revenue recognized from gift card liability balance at the beginning of the year	$	446	$	443	$	2,923	$	2,890

FAIR VALUE OF FINANCIAL INSTRUMENTS (Tables)

9 Months Ended

Sep. 26, 2021

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Mutual Fund Investments and Deferred Compensation Obligations

As of September 26, 2021 and December 27, 2020, the fair value of the mutual fund investments and deferred compensation obligations were as follows:


	September 26, 2021						December 27, 2020
	Level 1		Level 2		Level 3		Level 1		Level 2		Level 3
Assets - Investments designated for deferred compensation plan
Cash/money accounts	$	1,447	$	—	$	—	$	481	$	—	$	—
Mutual Funds	2,776		—		—		3,643		—		—
Total assets	$	4,223	$	—	$	—	$	4,124	$	—	$	—

INVENTORIES (Tables)

9 Months Ended

Sep. 26, 2021

Inventory Disclosure [Abstract]

Schedule of Inventories

Inventories consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
Raw materials	$	2,705	$	3,999
Work in progress	99		112
Finished goods	1,168		715
Consigned inventory	427		249
	$	4,399	$	5,075

PROPERTY & EQUIPMENT, NET (Tables)

9 Months Ended

Sep. 26, 2021

Property, Plant and Equipment [Abstract]

Schedule of Property and Equipment, net

Property and equipment, net consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
Land improvements	$	15,347	$	15,039
Furniture, fixtures, and equipment	112,930		105,059
Leasehold improvements	130,093		115,695
Transportation equipment	2,203		2,285
Construction-in-progress	12,206		10,711
	272,779		248,789
Less accumulated depreciation	(86,158)		(74,020)
	$	186,621	$	174,769

GOODWILL & INTANGIBLE ASSETS (Tables)

9 Months Ended

Sep. 26, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Indefinite-Lived Intangibles, net

Intangibles, net consisted of the following (in thousands):


	As of September 26, 2021

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(20,705)		35,412
Covenants not-to-compete	40,799		(40,799)		—
Favorable rental contracts	2,991		(1,787)		1,204
	$	323,832	$	(63,291)	$	260,541

	As of December 27, 2020

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(18,538)		37,579
Covenants not-to-compete	40,799		(37,515)		3,284
Favorable rental contracts	2,991		(1,599)		1,392
	$	323,832	$	(57,652)	$	266,180

Schedule of Finite-Lived Intangibles, net

Intangibles, net consisted of the following (in thousands):


	As of September 26, 2021

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(20,705)		35,412
Covenants not-to-compete	40,799		(40,799)		—
Favorable rental contracts	2,991		(1,787)		1,204
	$	323,832	$	(63,291)	$	260,541

	As of December 27, 2020

	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount

Indefinite-lived intangible assets:
Trade names	$	223,925	$	—	$	223,925
Intangibles subject to amortization:
Recipes	56,117		(18,538)		37,579
Covenants not-to-compete	40,799		(37,515)		3,284
Favorable rental contracts	2,991		(1,599)		1,392
	$	323,832	$	(57,652)	$	266,180

EQUITY METHOD INVESTMENT (Tables)

9 Months Ended

Sep. 26, 2021

Equity Method Investments and Joint Ventures [Abstract]

Schedule of Equity Method Investment Financial Information

A summary of financial information for C&O is as follows (in thousands):


	September 26, 2021		December 27, 2020
Assets:
Current assets	$	2,058	$	1,349
Property, plant, and equipment, net of accumulated depreciation $5,921 and $5,838 in 2021 and 2020, respectively	821		837
Total assets	2,879		2,186

Liabilities:
Current liabilities	709		681
Non-current liabilities
Deferred rent	1,206		1,193
Total liabilities	1,915		1,874

Members’ equity	964		312
Total liabilities and members' equity	$	2,879	$	2,186


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Results from operations:
Sales	$	3,608	$	2,815	$	9,205	$	8,480
Net income	585		242		1,303		707

DEBT (Tables)

9 Months Ended

Sep. 26, 2021

Debt Disclosure [Abstract]

Schedule of Long-term Debt

Debt consisted of the following (in thousands):


	September 26, 2021		December 27, 2020
First Lien Term B-3 Loans	$	326,583	$	329,076
Revolving Loans	—		—
Second Lien Term B-3 Loans	155,000		155,000
Unamortized discount and debt issuance costs	(11,495)		(14,372)
Total debt, net	470,088		469,704
Less: current portion	(3,324)		(3,324)
Long-term debt, net	$	466,764	$	466,380

- Definition

Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer.

+ References

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+ Details

EARNINGS (LOSS) PER UNIT (Tables)

9 Months Ended

Sep. 26, 2021

Earnings Per Share [Abstract]

Schedule of Computations of Basic and Diluted Earnings (Loss) per Unit


	Quarter Ended				Three Quarters Ended
	September 26, 2021		September 27, 2020		September 26, 2021		September 27, 2020
Net income	$	6,531	$	8,104	$	20,404	$	7,371
Less: Redeemable Preferred Units Accretion	(5,886)		(5,282)		(16,978)		(15,240)
Net income (loss) attributable to common unit holders	$	645	$	2,822	$	3,426	$	(7,869)

Units:
Weighted-average number of common units outstanding-basic	51,210,222		51,192,285		51,201,100		51,187,878
Dilutive unit awards	371,463		217,717		367,934		—
Weighted-average number of common units outstanding-diluted	51,581,685		51,410,002		51,569,034		51,187,878

Basic net income (loss) per unit	$	0.01	$	0.06	$	0.07	$	(0.15)
Diluted net income (loss) per unit	$	0.01	$	0.05	$	0.07	$	(0.15)

Schedule of Units Excluded from Calculation of Diluted Earnings per Share

The following units were excluded from the calculation of diluted earnings per share because they would be anti-dilutive:


	Quarter Ended		Three Quarters Ended
	September 26, 2021	September 27, 2020	September 26, 2021	September 27, 2020
Units subject to performance conditions	318,514	57,729	318,704	57,729
Units that were antidilutive	—	—	—	216,926
Total units excluded from diluted income (loss) per unit	318,514	57,729	318,704	274,655

STOCKHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands		9 Months Ended
	Aug. 11, 2021	Sep. 26, 2021	Sep. 27, 2020	Dec. 27, 2020
Temporary Equity [Line Items]
Common units issued (in shares)		51,210,222		51,192,434
Proceeds from issuance of common units		$ 100	$ 25
Common stock, par value (in dollars per share)		$ 0.01
Portillo's Inc.
Temporary Equity [Line Items]
Common units issued (in shares)	100	100
Proceeds from issuance of common units	$ 1
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01

DESCRIPTION OF BUSINESS (Details)	Sep. 26, 2021 foodProductionCommissary restaurant	Dec. 27, 2020 restaurant	Sep. 27, 2020 restaurant
Schedule of Equity Method Investments [Line Items]
Number of food production commissaries \| foodProductionCommissary	2
Number of restaurants	66	63
Number of non-traditional locations	3		4
C&O
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)		9 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	Oct. 20, 2021	Sep. 26, 2021 USD ($) segment $ / shares	Dec. 27, 2020 USD ($)
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) \| $ / shares		$ 0.01
Deferred offering costs \| $		$ 4,600,000	$ 0
Number of operating segments		1
Number of reportable segments		1
Subsequent Event
Subsequent Event [Line Items]
Reverse stock split, conversion ratio	0.1351

REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020	Dec. 27, 2020
Revenue from External Customer [Line Items]
Gift card sales that will not be redeemed, percent	11.00%		11.00%
Gift card breakage	$ 100	$ 100	$ 554	$ 556
Revenue recognized from gift card liability balance at the beginning of the year	446	$ 443	2,923	$ 2,890
Gift Card
Revenue from External Customer [Line Items]
Gift card liability	$ 3,852		$ 3,852		$ 6,216

FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 26, 2021	Dec. 27, 2020
Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	$ 4,223	$ 4,124
Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	0	0
Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	0	0
Cash/money accounts \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	1,447	481
Cash/money accounts \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	0	0
Cash/money accounts \| Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	0	0
Mutual Funds \| Level 1
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	2,776	3,643
Mutual Funds \| Level 2
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	0	0
Mutual Funds \| Level 3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Investments, fair value	$ 0	$ 0

INVENTORIES (Details) - USD ($) $ in Thousands	Sep. 26, 2021	Dec. 27, 2020
Inventory Disclosure [Abstract]
Raw materials	$ 2,705	$ 3,999
Work in progress	99	112
Finished goods	1,168	715
Consigned inventory	427	249
Total inventory	$ 4,399	$ 5,075

PROPERTY & EQUIPMENT, NET (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020	Dec. 27, 2020
Property, Plant and Equipment [Line Items]
Property and equipment	$ 272,779		$ 272,779		$ 248,789
Less accumulated depreciation	(86,158)		(86,158)		(74,020)
Total property and equipment	186,621		186,621		174,769
Depreciation expense	4,300	$ 3,900	12,600	$ 11,800
Land improvements
Property, Plant and Equipment [Line Items]
Property and equipment	15,347		15,347		15,039
Furniture, fixtures, and equipment
Property, Plant and Equipment [Line Items]
Property and equipment	112,930		112,930		105,059
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment	130,093		130,093		115,695
Transportation equipment
Property, Plant and Equipment [Line Items]
Property and equipment	2,203		2,203		2,285
Construction-in-progress
Property, Plant and Equipment [Line Items]
Property and equipment	$ 12,206		$ 12,206		$ 10,711

GOODWILL & INTANGIBLE ASSETS - Summary of Intangible Assets, Net (Details) - USD ($) $ in Thousands	Sep. 26, 2021	Dec. 27, 2020
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets:	$ 223,925	$ 223,925
Accumulated Amortization	(63,291)	(57,652)
Gross Carrying Amount	323,832	323,832
Net Carrying Amount	260,541	266,180
Recipes
Finite-Lived Intangible Assets [Line Items]
Intangibles subject to amortization, gross	56,117	56,117
Accumulated Amortization	(20,705)	(18,538)
Intangibles subject to amortization, net	35,412	37,579
Covenants not-to-compete
Finite-Lived Intangible Assets [Line Items]
Intangibles subject to amortization, gross	40,799	40,799
Accumulated Amortization	(40,799)	(37,515)
Intangibles subject to amortization, net	0	3,284
Favorable rental contracts
Finite-Lived Intangible Assets [Line Items]
Intangibles subject to amortization, gross	2,991	2,991
Accumulated Amortization	(1,787)	(1,599)
Intangibles subject to amortization, net	$ 1,204	$ 1,392

GOODWILL & INTANGIBLE ASSETS - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2021 USD ($)	Sep. 27, 2020 USD ($)	Sep. 26, 2021 USD ($) reporting_unit	Sep. 27, 2020 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Number of reporting units \| reporting_unit			1
Amortization expense	$ 1.2	$ 2.2	$ 5.6	$ 6.6
Intangible asset, expected amortization, remainder of year	0.8		0.8
Intangible asset, expected amortization, year one	3.1		3.1
Intangible asset, expected amortization, year two	3.1		3.1
Intangible asset, expected amortization, year three	3.0		3.0
Intangible asset, expected amortization, year four	3.0		3.0
Intangible asset, expected amortization, year five	2.9		2.9
Intangible asset, expected amortization, thereafter	$ 20.7		$ 20.7

EQUITY METHOD INVESTMENT (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
EQUITY METHOD INVESTMENT (Details) - USD ($) $ in Thousands	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020	Jun. 27, 2021	Dec. 27, 2020	Jun. 28, 2020	Dec. 29, 2019
Assets:
Current assets	$ 67,128		$ 67,128			$ 54,626
Property and equipment, net	186,621		186,621			174,769
Accumulated depreciation	86,158		86,158			74,020
Total assets	929,462		929,462			910,222
Liabilities:
Current liabilities	62,266		62,266			66,352
Deferred rent	30,844		30,844			26,694
Total liabilities	566,736		566,736			568,942
Members’ equity	145,177	$ 140,704	145,177	$ 140,704	$ 144,113	140,709	$ 137,670	$ 147,734
Total liabilities and members' equity	929,462		929,462			910,222
Results from operations:
Net income	$ 6,531	8,104	$ 20,404	7,371
C&O
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%		50.00%
Assets:
Current assets	$ 2,058		$ 2,058			1,349
Property and equipment, net	821		821			837
Accumulated depreciation	5,921		5,921			5,838
Total assets	2,879		2,879			2,186
Liabilities:
Current liabilities	709		709			681
Deferred rent	1,206		1,206			1,193
Total liabilities	1,915		1,915			1,874
Members’ equity	964		964			312
Total liabilities and members' equity	2,879		2,879			$ 2,186
Results from operations:
Sales	3,608	2,815	9,205	8,480
Net income	$ 585	$ 242	$ 1,303	$ 707

DEBT - Summary of Debt (Details) - USD ($) $ in Thousands	Sep. 26, 2021	Dec. 27, 2020
Debt Instrument [Line Items]
Unamortized discount and debt issuance costs	$ (11,495)	$ (14,372)
Total debt, net	470,088	469,704
Current portion of long-term debt	(3,324)	(3,324)
Long-term debt, net of current portion	466,764	466,380
Line of Credit
Debt Instrument [Line Items]
Long-term debt, gross		0
First Lien Term B-3 Loans
Debt Instrument [Line Items]
Long-term debt, gross	326,583	329,076
Second Lien Term B-3 Loans
Debt Instrument [Line Items]
Long-term debt, gross	$ 155,000	$ 155,000

- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References + Details

DEBT - Narrative (Details) - USD ($)					3 Months Ended		9 Months Ended
DEBT - Narrative (Details) - USD ($)	Oct. 25, 2021	Sep. 26, 2021	Sep. 27, 2020	Dec. 06, 2019	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020	Dec. 27, 2020	Aug. 01, 2014
Debt Instrument [Line Items]
Payments of long-term debt							$ 2,493,000	$ 12,493,000
Debt issuance costs				$ 14,500,000
Debt issuance costs, capitalized amount				13,300,000
Debt issuance costs, amount expensed				1,200,000
Amortization of debt issuance costs					$ 600,000	$ 600,000	1,700,000	1,700,000
Amortization of debt discount					400,000	400,000	1,200,000	1,200,000
Interest expense					$ 10,683,000	$ 10,766,000	$ 32,124,000	$ 34,298,000
Subsequent Event \| IPO
Debt Instrument [Line Items]
Proceeds from public offering	$ 429,900,000
Revolving Loans
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity										$ 30,000,000
Interest rate at period end		3.25%	3.50%		3.25%	3.50%	3.25%	3.50%
Line of credit		$ 0			$ 0		$ 0		$ 0
Commitment fee percentage		0.25%	0.375%
Remaining borrowing capacity		$ 44,700,000			44,700,000		44,700,000
Letter of Credit
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity										7,500,000
Line of credit		$ 5,300,000			$ 5,300,000		$ 5,300,000		$ 5,800,000
Fronting fee, percentage		0.125%	0.125%		0.125%	0.125%	0.125%	0.125%
First Lien Term B-3 Loans
Debt Instrument [Line Items]
Debt, principal amount				332,400,000
Interest rate, effective percentage		7.80%	7.52%		7.80%	7.52%	7.80%	7.52%
Debt instrument, periodic payment, principal					$ 800,000
First Lien Term B-3 Loans \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, increase (decrease) in basis spread on variable rate		1.00%			1.00%		1.00%
Debt instrument, basis spread on variable rate							5.50%
Interest rate at period end		6.50%			6.50%		6.50%
First Lien Term B-3 Loans \| Term Loans
Debt Instrument [Line Items]
Debt, principal amount										335,000,000
First Lien Term B-3 Loans \| Revolving Loans
Debt Instrument [Line Items]
Debt, limit increase				50,000,000
Second Lien Term B-3 Loans
Debt Instrument [Line Items]
Debt, principal amount				$ 155,000,000						$ 80,000,000
Interest rate at period end		10.75%			10.75%		10.75%
Interest rate, effective percentage		12.22%	11.90%		12.22%	11.90%	12.22%	11.90%
Second Lien Term B-3 Loans \| Subsequent Event
Debt Instrument [Line Items]
Payments of long-term debt	$ 158,100,000
Second Lien Term B-3 Loans \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument, increase (decrease) in basis spread on variable rate				15000.00%
Debt instrument, basis spread on variable rate				9.50%

REDEEMABLE PREFERRED UNITS (Details) - USD ($) $ in Thousands	Oct. 25, 2021	Aug. 01, 2014	Sep. 26, 2021	Jun. 27, 2021	Dec. 27, 2020	Sep. 27, 2020	Jun. 28, 2020
Class of Stock [Line Items]
Redeemable preferred units outstanding (in shares)		100,000	100,000	100,000		100,000	100,000
Capital contribution		$ 97,700
Increase to preferred rate due to triggering event, percent		2.00%
Redeemable preferred units, liquidation preference, percent			101.00%
Redeemable preferred units, value			$ 217,549	$ 211,663	$ 200,571	$ 195,287	$ 190,005
Preferred Rate, Annual Increase Until Eighth Anniversary
Class of Stock [Line Items]
Redeemable preferred units, percent accretion per year		11.00%
Preferred Rate, Annual Increase, Eighth To Tenth Anniversary
Class of Stock [Line Items]
Redeemable preferred units, percent accretion per year		12.00%
Preferred Rate, Annual Increase, Thereafter
Class of Stock [Line Items]
Redeemable preferred units, percent accretion per year		13.00%
Subsequent Event
Class of Stock [Line Items]
Redeemable preferred units outstanding (in shares)	0
Repayment of redeemable preferred units	$ 221,700
IPO \| Subsequent Event
Class of Stock [Line Items]
Proceeds from public offering	$ 429,900

COMMON UNITS AND UNIT-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020	Dec. 27, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common units issued (in shares)	51,210,222		51,210,222		51,192,434
Common units outstanding (in shares)	51,210,222		51,210,222		51,192,434
Option exercise price range, lower limit (in dollars per share)			$ 3.25
Option exercise price range, higher limit (in dollars per share)			$ 5.77
Cash compensation expense	$ 0.2	$ 0.2	$ 0.4	$ 0.6
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options authorized (in shares)					7,477,256
Options available for issuance (in shares)	40,558		40,558
Termination period			10 years
Vesting period			5 years
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of common units (in shares)			131,578

CONTINGENCIES (Details) - USD ($) $ in Millions	3 Months Ended
CONTINGENCIES (Details) - USD ($) $ in Millions	Sep. 26, 2021	Dec. 27, 2020
Commitments and Contingencies Disclosure [Abstract]
Loss contingency accrual	$ 0.0	$ 0.9
Loss contingency, loss in period	$ 0.8

RELATED PARTY TRANSACTIONS (Details) $ in Thousands		3 Months Ended		9 Months Ended
RELATED PARTY TRANSACTIONS (Details) $ in Thousands	Aug. 13, 2021 USD ($)	Sep. 26, 2021 USD ($) property shares	Sep. 27, 2020 USD ($)	Sep. 26, 2021 USD ($) property shares	Sep. 27, 2020 USD ($)	Dec. 27, 2020 USD ($) shares	Dec. 29, 2019 USD ($) shares
Related Party Transaction [Line Items]
Common units issued (in shares) \| shares		51,210,222		51,210,222		51,192,434
Stock subscription receivable		$ 0		$ 0		$ 499
Equity Method Investee \| C&O
Related Party Transaction [Line Items]
Accounts receivable, related parties		300		300		200
CEO
Related Party Transaction [Line Items]
Common units issued (in shares) \| shares							195,933
Stock subscription receivable		0		0		500	$ 1,000
Proceeds from subscriptions received	$ 200
Director
Related Party Transaction [Line Items]
Related party expenses		300	$ 300	700	$ 900
Accounts payable, related parties		0		0		$ 200
Director \| Cost of Goods Sold
Related Party Transaction [Line Items]
Related party expenses		200	200	400	600
Director \| Other Operating Expenses
Related Party Transaction [Line Items]
Related party expenses		$ 100	100	$ 300	300
Former CEO
Related Party Transaction [Line Items]
Number of leased properties \| property		23		23
Rent payments		$ 2,000	$ 1,900	$ 5,900	$ 5,600
Consulting fees		$ 2,000		$ 2,000

EARNINGS (LOSS) PER UNIT - Schedule of Basic and Diluted Earnings (Loss) per Unit (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Earnings Per Share [Abstract]
Net income	$ 6,531	$ 8,104	$ 20,404	$ 7,371
Redeemable preferred units accretion	(5,886)	(5,282)	(16,978)	(15,240)
Net income (loss) attributable to common unit holders	$ 645	$ 2,822	$ 3,426	$ (7,869)
Units:
Weighted average number of common units outstanding - basic (in shares)	51,210,222	51,192,285	51,201,100	51,187,878
Diluted unit awards	371,463	217,717	367,934	0
Weighted average number of common units outstanding - diluted (in shares)	51,581,685	51,410,002	51,569,034	51,187,878
Basic net income (loss) per unit (in dollars per share)	$ 0.01	$ 0.06	$ 0.07	$ (0.15)
Diluted net income (loss) per unit (in dollars per share)	$ 0.01	$ 0.05	$ 0.07	$ (0.15)

EARNINGS (LOSS) PER UNIT - Schedule of Units Excluded from Calculation of Diluted Earnings per Share (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 26, 2021	Sep. 27, 2020	Sep. 26, 2021	Sep. 27, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Units excluded from diluted income (loss) per unit (in shares)	318,514	57,729	318,704	274,655
Units subject to performance conditions
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Units excluded from diluted income (loss) per unit (in shares)	318,514	57,729	318,704	57,729
Units that were antidilutive
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Units excluded from diluted income (loss) per unit (in shares)	0	0	0	216,926

SUBSEQUENT EVENTS (Details) $ / shares in Units, $ in Thousands				3 Months Ended			9 Months Ended
	Nov. 18, 2021 restaurant	Oct. 25, 2021 USD ($) $ / shares shares	Oct. 20, 2021	Dec. 26, 2021 USD ($)	Sep. 26, 2021 USD ($) restaurant $ / shares shares	Sep. 27, 2020 USD ($) shares	Sep. 26, 2021 USD ($) restaurant $ / shares shares	Sep. 27, 2020 USD ($) shares	Jun. 27, 2021 shares	Dec. 27, 2020 restaurant shares	Jun. 28, 2020 shares	Aug. 01, 2014 shares
Subsequent Event [Line Items]
Common stock, par value (in dollars per share) \| $ / shares					$ 0.01		$ 0.01
Underwriting fees and commissions							$ 2,108	$ 0
Number of restaurants \| restaurant					66		66			63
Payments of long-term debt							$ 2,493	12,493
Cash compensation expense					$ 200	$ 200	400	600
Noncash compensation expense							$ 443	$ 564
Common units outstanding (in shares) \| shares					51,210,222		51,210,222			51,192,434
Common units issued (in shares) \| shares					51,210,222		51,210,222			51,192,434
Redeemable preferred units outstanding (in shares) \| shares					100,000	100,000	100,000	100,000	100,000		100,000	100,000
Options
Subsequent Event [Line Items]
Share-based compensation not yet recognized, amount					$ 12,700		$ 12,700
Share-based compensation not yet recognized, period for recognition							4 years 6 months
Options available for issuance (in shares) \| shares					40,558		40,558
Forecast \| Options
Subsequent Event [Line Items]
Payments of option substitution bonus				$ 6,300
Noncash compensation expense				1,300
Noncash compensation expense				$ 23,300
C&O
Subsequent Event [Line Items]
Ownership percentage					50.00%		50.00%
Subsequent Event
Subsequent Event [Line Items]
Sale of stock, price per share (in dollars per share) \| $ / shares		$ 20.00
Number of new restaurants \| restaurant	1
Number of restaurants \| restaurant	67
Repayment of redeemable preferred units		$ 221,700
Payments for repurchase of common stock		$ 57,000
Reverse stock split, conversion ratio			0.1351
Tax payable as a percent of tax savings		85.00%
Tax savings retained, percent		15.00%
Redeemable preferred units outstanding (in shares) \| shares		0
Redeemable preferred units issued (in shares) \| shares		0
Subsequent Event \| Common Class A
Subsequent Event [Line Items]
Common units outstanding (in shares) \| shares		35,807,171
Common units issued (in shares) \| shares		35,807,171
Subsequent Event \| Common Class B
Subsequent Event [Line Items]
Common units outstanding (in shares) \| shares		35,673,321
Common units issued (in shares) \| shares		35,673,321
Subsequent Event \| 2021 Plan
Subsequent Event [Line Items]
Options available for issuance (in shares) \| shares		7,148,049
Subsequent Event \| Second Lien Term B-3 Loans
Subsequent Event [Line Items]
Payments of long-term debt		$ 158,100
Subsequent Event \| IPO
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares		23,310,810
Proceeds from public offering		$ 429,900
Underwriting fees and commissions		29,100
Offering expenses		$ 7,200
Subsequent Event \| Over-Allotment Option
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) \| shares		3,040,540