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Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954510 - Disclosure - NON-CONTROLLING INTERESTS - Schedule of LLC interest Ownership by Portillo's Inc. and Pre-IPO LLC Members (Details) link:presentationLink link:calculationLink link:definitionLink 9954511 - Disclosure - NON-CONTROLLING INTERESTS - Changes in Ownership in Portillo's OpCo on the Company’s Equity (Details) link:presentationLink link:calculationLink link:definitionLink 9954512 - Disclosure - EQUITY-BASED COMPENSATION - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9954513 - Disclosure - EQUITY-BASED COMPENSATION - Restricted Stock Units and Performance Stock Options (Details) link:presentationLink link:calculationLink link:definitionLink 9954514 - Disclosure - EQUITY-BASED COMPENSATION - Schedule of Fair Value and Weighted Average Assumptions (Details) link:presentationLink link:calculationLink link:definitionLink 9954515 - Disclosure - EQUITY-BASED COMPENSATION - 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