
☑ANNUALREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934ForthefiscalyearendedDecember31,2025or☐TRANSITIONREPORTPURSUANTTOSECTION13OR15(d)OFTHESECURITIESEXCHANGEACTOF1934ForthetransitionperiodfromtoCommissionfilenumber:001-13461 Group1Automotive,Inc. (Exactnameofregistrantasspecifiedinitscharter) 76-0506313 Delaware (I.R.S.EmployerIdentificationNo.) (713)647-5700(Registrant’stelephonenumber,includingareacode)NotApplicable(Formername,formeraddressandformerfiscalyear,ifchangedsincelastreport) SecuritiesregisteredpursuanttoSection12(b)oftheAct: Nameofexchangeonwhichregistered NewYorkStockExchange Commonstock,parvalue$0.01pershare Indicatebycheckmarkiftheregistrantisawell-knownseasonedissuer,asdefinedinRule405oftheSecuritiesAct.YesþNo¨IndicatebycheckmarkiftheregistrantisnotrequiredtofilereportspursuanttoSection13orSection15(d)oftheAct.Yes¨Noþ Indicatebycheckmarkwhethertheregistrant(1)hasfiledallreportsrequiredtobefiledbySection13or15(d)oftheSecuritiesExchangeActof1934duringthepreceding12months(orforsuchshorterperiodthattheregistrantwasrequiredtofilesuchreports),and(2)hasbeensubjecttosuchfilingrequirementsforthepast90days.YesþNo¨ IndicatebycheckmarkwhethertheregistranthassubmittedelectronicallyeveryInteractiveDataFilerequiredtobesubmittedpursuanttoRule405ofRegulationS-T(§232.405ofthischapter)duringthepreceding12months(orforsuchshorterperiodthattheregistrantwasrequiredtosubmitsuchfiles).YesþNo¨ Indicatebycheckmarkwhethertheregistrantisalargeacceleratedfiler,anacceleratedfiler,anon-acceleratedfiler,asmallerreportingcompanyoranemerginggrowthcompany.Seethedefinitionsof“largeacceleratedfiler,”“acceleratedfiler,”“smallerreportingcompany”and“emerginggrowthcompany”inRule12b-2oftheExchangeAct.(Checkone): ¨Acceleratedfiler☐Smallerreportingcompany☐Emerginggrowthcompany LargeacceleratedfilerþNon-acceleratedfiler¨ Ifanemerginggrowthcompany,indicatebycheckmarkifthatregistranthaselectednottousetheextendedtransitionperiodforcomplyingwithanyneworrevisedfinancialaccountingstandardsprovidedpursuanttoSection13(a)oftheExchangeAct.¨ Indicatebycheckmarkwhethertheregistranthasfiledareportonandattestationtoitsmanagement’sassessmentoftheeffectivenessofitsinternalcontroloverfinancialreportingunderSection404(b)oftheSarbanes-OxleyAct(15U.S.C.7262(b))bytheregisteredpublicaccountingfirmthatpreparedorissueditsauditreport.☑ IfsecuritiesareregisteredpursuanttoSection12(b)oftheAct,indicatebycheckmarkwhetherthefinancialstatementsoftheregistrantincludedinthefilingreflectthecorrectionofanerrortopreviouslyissuedfinancialstatements.¨ Indicatebycheckmarkwhetheranyofthoseerrorcorrectionsarerestatementsthatrequiredarecoveryanalysisofincentive-basedcompensationreceivedbyanyoftheregistrant’sexecutiveofficersduringtherelevantrecoveryperiodpursuantto§240.10D-1(b).¨ Indicatebycheckmarkwhethertheregistrantisashellcompany(asdefinedinRule12b-2oftheAct).Yes☐Noþ Theaggregatemarketvalueofcommonstockheldbynon-affiliatesoftheregistrantwasapproximately$5.5billionbasedonthereportedlastsalepriceofcommonstockonJune30,2025,whichwasthelastbusinessdayoftheregistrant’smostrecentlycompletedsecondquarter.AsofFebruary6,2026,therewere11,925,199sharesofourcommonstock,parvalue$0.01pershare,outstanding. DOCUMENTSINCORPORATEDBYREFERENCE Portionsoftheregistrant’sdefinitiveproxystatementforits2026AnnualMeetingofStockholders,whichwillbefiledwiththeSecuritiesandExchangeCommissionwithin120daysofDecember31,2025,areincorporatedbyreferenceintoPartIIIofthisForm10-K. TABLEOFCONTENTS GLOSSARYOFDEFINITIONS1CAUTIONARYSTATEMENTABOUTFORWARD-LOOKINGSTATEMENTS2PARTI3Item1.Business3Item1A.RiskFactors12Item1B.UnresolvedStaffComments23Item1C.Cybersecurity23Item2.Properties25Item3.LegalProceedings25Item4.MineSafetyDisclosures25 PARTII 26Item5.MarketforRegistrantCommonEquity,RelatedStockholderMattersandIssuerPurchasesofEquitySecurities26Item6.[Reserved]27Item7.Management’sDiscussionandAnalysisofFinancialConditionandResultsofOperations28Item7A.QuantitativeandQualitativeDisclosuresAboutMarketRisk45Item8.FinancialStatementsandSupplementaryData46Item9.ChangesinandDisagreementswithAccountantsonAccountingandFinancialDisclosure46Item9A.ControlsandProcedures46Item9B.OtherInformation49Item9C.Disclosur