SEC Form 6-K filed by Banco Santander Brasil SA

MANUAL FOR ATTENDANCE AT THE EXTRAORDINARY GENERAL MEETING August 18, 2026 1 MANAGEMENT INVITATION I TEMPLATE OF POWER OF ATTORNEY 3 ATTENDANCEAT THE MEETING II RÉSUMÉ OF THE CANDIDATES EXHIBITS: 2 CALL NOTICE 4 INFORMATION ABOUT THE AGENDA 3 1. MANAGEMENT INVITATION DearShareholder, ItiswithgreatpleasurethatIinviteyou,ashareholderofSantanderBrasil,toparticipateinourExtraordinaryGeneralMeeting(“EGM”). ThisManualwaspreparedtoassistyouinunderstandingthematterspresented,providingaconsciousandreasoneddecision-makingprocess,anticipatingpossibleclarificationsandvotingguidelines. Inordertofacilitateyouranalysisandappreciationofthematterstoberesolved,thisManualincludestheinformationmadeavailableinadditiontotheCallNotice. ThisManualmustbereadtogetherwiththeManagementProposalandotherdocumentsrelatedtoourGeneralMeeting,availableontheCompany'sinvestorrelationswebsite(www.ri.santander.com.br),ontheCVMwebsite(www.cvm.gov.br)andontheB3website(www.b3.com.br). Weareatyourdisposaltoclarifyanyquestionsthroughtheemailsacionistas@santander.com.brorientedatnon-financialindividualandcorporateinvestorsandri@santander.com.brforinstitutionalinvestors. WehopethatthisManualfulfillsitspurposeinassistingyourdecisionmaking.YourparticipationisessentialfortheCompany. Avenida Presidente Juscelino Kubitschek, nº 2041 –mezzanine, Vila Nova Conceição, São Paulo/SP 08/18/2026 3:00 P.M. (BRT) Local: Date & Time: 4 2. CALL NOTICE BANCO SANTANDER (BRASIL) S.A. Publicly-Held Company with Authorized Capital CNPJ/MF 90.400.888/0001-42 -NIRE 35.300.332.067 CALLNOTICE–EXTRAORDINARYGENERALMEETING-ShareholdersareherebyinvitedtoattendtheExtraordinaryGeneralMeeting("EGM")tobeheldonAugust18,2026,at3:00P.M.,attheCompany'sheadquarters,locatedatAvenidaPresidenteJuscelinoKubitscheknº2041–mezzanine,VilaNovaConceição,SãoPaulo/SP,toresolveonthefollowingAgenda: (a) FIXthenumberofmembersthatwillcomposetheBoardofDirectorsoftheCompany ; (b) ELECTtwo(2)newmemberstocomposetheCompany'sBoardofDirectors;and (c)Asaresultoftheresolutioninthepreviousitem,CONFIRMthecompositionoftheCompany'sBoardofDirectors. ObservationsforparticipationandVotingduringtheMeeting ParticipationintheMeeting:Shareholders,theirlegalrepresentativesorattorneys-in-factmayparticipateintheMeetinginanyofthefollowingways: Inperson-TheshareholdersortheirlegalrepresentativesshallpresentthemselvesfortheEGMwiththeappropriateidentitydocuments.Intheeventofrepresentationofashareholderbyanattorney-in-fact,shareholdersshallprovidetheCompanywithapowerofattorneygrantedaccordingtotheapplicablelaw,tobedeliveredattheCompany'sHeadquarters,atleastseventy-two(72)hoursbeforetheEGMisheld; RemoteVotingBallot:theCompanyimplementedtheremotevotingsystempursuanttoCVMResolution81/22,asamended,enablingourShareholderstosendremotevotingballotsdirectlytotheCompany,tothebookkeeper,totherespectivecustodianagentsortotheCentralDepository,inaccordancewiththeproceduresdescribedintheGeneralMeetingParticipationManual.AsprovidedforinArticle5,§4,ofCVMResolutionNo.81/22,withtheamendmentsintroducedbyCVMResolutionsNo.59/21and204/24,theCompanyunderstandsthatholdingtheEGMinpersonallowsforacloserenvironmentbetweenshareholdersandtheattendingCompany'smanagement,facilitatingtheclarificationofdoubtsandthediscussionofrelevantmatters,enablingacloserenvironmenttodeliberationsanddecision-making.Inaddition,itensuresgreatersecurityinthetransmissionofinformation,avoidingrisksassociatedwithtechnicalorcyberfailures. 5 2. CALL NOTICE Inthissense,theCompanyrecommendsandencouragestheparticipationofitsshareholdersinitsMeeting,usingthevariousparticipationchannelsmadeavailable,whetherthroughtheuseofremotevotinginstruments,throughtheavailableelectronicmeansorevenbysendingwrittenvotestotheCompanyorgrantingstandardizedproxieswithvotinginstructions,inaccordancewiththeinstructionsmadeavailableintheManagementProposalfortheExtraordinaryGeneralMeetingofAugust18,2026. General Instructions 1.AsprovidedinCVMResolutionNo.70/22,theminimumpercentageofparticipationinthevotingcapitalrequiredfortheapplicationofthecumulativevotingprocess(processodevotomúltiplo)fortheelectionofthemembersoftheBoardofDirectorsisof5%;2.Asprovidedin§2ofarticle161ofLawNo.6,404/76andart.4ofCVMResolutionNo.70/22,theinstallationofaFiscalCouncilbytheGeneralMeetingshalloccurattherequestofshareholdersrepresentingatleast2%(twopercent)ofthecommonshares,or1%(onepercent)ofpreferredshares;and 3.ThedocumentsrelatedtothematterstobeexaminedandresolvedattheEGMareavailabletoshareholders(i)attheCompany'sheadquarters,atAvenidaPresidenteJuscelinoKubitschek,nº2041,WtorreJK,9thfloor-CorporateLegalDepartment,wheretheycanbeconsultedonbusinessdays,from10:00a.m.until4:00p.m.,andonitsinvestorrelationswebsite (www.ri.santander.com.br–atCorporateGovernance>>MinutesoftheMeeting);(ii)onthewebsiteoftheCVM–ComissãodeValoresMobiliários(www.cvm.gov.br)and(iii)onthewebsiteofthestockexchangeB3S.A.-Brasil,Bolsa,Balcão( http : //www . b 3 . com . br ). SãoPaulo,July16,2026 DeborahSternVieitas ChairwomanoftheBoardofDirectors 6 3. ATTENDANCE AT THE MEETING SantanderBrasilshareholdersmayparticipateintheEGMinpersonorbyproxy,asspecifiedinitem3.2beloworevenbyRemoteVotingBallot.ShareholderswillberequiredtoprovidethefollowingdocumentstoparticipateintheEGM. 3.1.In-personParticipation SantanderBrasilshareholdersmayparticipateintheEGMbyattendingtheplacewhereitwillbeheldanddeclaringtheirvote,accordingtothetypesofsharestheyown(commonand/orpreferred),andthematterstobevotedon. Corporateshareholders,suchascompaniesandinvestmentfunds,shallberepresentedinaccordancewiththeirArticlesofAssociation,ArticlesofOrganizationorBylaws,deliveringdocumentsprovingtheregularityoftherepresentation,accompaniedbytheMinutesoftheelectionoftheManagers,ifapplicable,attheplaceandtermindicatedintheitembelow.PriortotheEGM,theshareholdersshallsigntheAttendanceBook.ShareholderswithoutvotingrightsmayattendtheEGManddiscussallmatterssubmittedforresolution. Individual: • identity document with photo (original or copy) • proof of ownership of the shares issued by the Company, issued by the depository and/or custodian financial institution (original or copy) Legal entity: • corporate documents that prove the legal representation of the shareholder (original or copy) • legal representative's identity document with photo (original or copy) Investmentfund: • identity document of the legal representative of the Investment Fund’s manager (or of the manager, as the case may be) with photo (original or copy) • simple copy of the last consolidated bylaws of the fund and of the Articles of Association or Organization of its manager, in addition to the corporate documentation granting powers of representation (minutes of election of the officers and/or power of attorney) 7 3. ATTENDANCE AT THE MEETING 3.2.ParticipationbyProxyTheshareholdermayberepresentedattheEGMbyanattorney-in-fact,dulyappointedunderapublicorprivateinstrument,andpursuanttoarticle126,§1oftheCorporationsAct,theattorneys-in-factshallhavebeenappointedlessthanone(1)yearago,andtheyshallbe(i)shareholdersoftheCompany,(ii)managersoftheCompany,(iii)lawyers,or(iv)financialinstitutions,withtheinvestmentfund’smanagerbeingresponsibleforrepresentingthequotaholders. TheoriginalsorcopiesofthedocumentsmentionedabovemaybedeliveredattheCompany'sprincipalplaceofbusinessbythetimetheEGMisheld. However,inordertofacilitateshareholders'accesstotheEGM,werecommendthatthedeliveryofsuchdocumentsbemadeatleastseventy-two(72)hoursbeforetheEGMisheld. Inthecaseofsubmittalofdocumentsviaemail,werequestthattheshareholdercontacttheCompany,sothattheoriginalsorcopiescanbedeliveredbythedaytheEGMisheld. IncasetheShareholderisunabletoattendtheEGMorcannotyetberepresentedbyanattorney-in-factofhis/her/theirchoice,theCompanywillmakeavailableanattorney-in-facttovotefortheshareholder,inaccordancewithhis/her/theirvotinginstructions,accordingtothepowerofattorneytemplateinExhibit1tothisManual. Furthermore,itshouldbenotedthatinadditiontothepowerofattorney,theshareholdershallforwardthedocumentsrequiredbytheCompanytoparticipateintheEGM,asprovidedforinitem3above. ThedocumentsshallbedeliveredattheCompany’sprincipalplaceofbusiness,atAvenidaPresidenteJuscelinoKubitschek,No.2041–BlocoA-VilaNovaConceição-SãoPaulo–SP,26thfloor–InvestorRelations,email:ri@santander.com.br. 3.3.RemoteVotingParticipation Pursuanttoarticles26etseq.ofCVMResolutionNo.81/22,theCompany'sshareholdersmayalsovoteatshareholders’meetingsbymeansofremotevoting,tobeformalizedthroughthe“remotevotingballot”(“Ballot”),thetemplateofwhichisavailableintheCorporateGovernanceareaoftheCompany’sInvestorRelationswebsite(www.ri.santander.com.br),oronthewebsiteoftheBrazilianSecuritiesandExchangeCommission–CVM(http://sistemas.cvm.gov.br/?CiaDoc). Theshareholderthatchoosestoexercisehis/her/theirvotingrightsremotelyshalldosobyoneoftheoptionsdescribedbelow: 8 3. ATTENDANCE AT THE MEETING (I)SubmittaloftheBallottoCustodyagentsorCentralDepository TheShareholderthatchoosestocastremotevotingthroughhis/her/itsrespectivecustodianagent(“Custodian")musttransmittheirvotinginstructionsinaccordancewiththerulesdeterminedbytheCustodian,whowillforwardsaidvotingstatementstotheCentralDepositoryofB3S.A.–Brasil,Bolsa,BalcãoordirectlyforwardthevotinginstructionstotheCentralDepositoryinaccordancewiththerulesdeterminedbyB3S.A.–Brasil,BolsaBalcão.ShareholdersmustcontacttheirrespectiveCustodiansandCentralDepositorytochecktheproceduresestablishedbythemforissuingvotinginstrutionsviaballot,aswellasthedocumentsandinformationrequiredforthispurpose. TheShareholdershallconveytheinstructionsforcompletionoftheBallottohis/her/theirCustodyagentsorCentralDepositoryby08/14/2026(including),unlessdefinedotherwisebythem. (II)SubmittaloftheBallotbytheShareholdertotheBookkeeper TheShareholderwhochoosestocasttheremotevotethroughtheCompany'sBookkeepershallobservethefollowinginstructions,sothattheBallotcanbedeemedvalidandthevotesarecounted: (i)allfieldsshallbedulycompleted; (ii)allpagesshallbeinitialed; (iii)thelastpageshallbesignedbytheShareholderorhis/her/theirlegalrepresentative(s),asapplicable,andinaccordancewiththeapplicablelegislation. ThesamedocumentslistedatthebeginningofthissectionforIndividuals,LegalEntitiesandInvestmentFundsmustbesenttotheBookkeeperby08 /14/2026(including)(i)atthefollowingaddress:BancoSantander(Brasil)S.A.–Shareholders–BookkeepingofShares–RuaAmadorBueno,474–2ndfloor–Setorvermelho-SantoAmaro–SãoPaulo/SP–CEP04752-005;or(ii)viaemail,totheelectronicaddressacoes@santander.com.br. Afterreceivingthedocuments,theBookkeeper,withinthree(3)days,willinformtheShareholderregardingthereceiptofthedocumentsandtheiracceptance.Ifthesubmitteddocumentationisnotconsideredsuitable,theBallotshallbeconsideredinvalid,andtheShareholdermayregularizeitby08 /14/2026(including). RemotevotingballotsreceivedbytheBookkeeperafter08 /14/2026shallbedisregarded. 9 3. ATTENDANCE AT THE MEETING (III)SubmittaloftheremotevotingballotdirectlytotheCompany TheShareholderwhochoosestocasttheremotevotethroughtheCompanyshallobservethefollowinginstructions,sothattheBallotcanbedeemedvalidandthevotesarecounted: (i)allfieldsshallbedulycompleted; (ii)allpagesshallbeinitialed; (iii)thelastpageshallbesignedbytheShareholderorhis/her/itslegalrepresentative(s),asapplicable,andinaccordancewiththeapplicablelegislation. ThesamedocumentslistedatthebeginningofthissectionforIndividuals,LegalEntitiesandInvestmentFundsmustbesenttotheCompanyby08/14/2026(including)(i)atthefollowingaddress:BancoSantander(Brasil)S.A.–InvestorRelations–AvenidaPresidenteJuscelinoKubitschek,2041–26ºandar–VilaNovaConceição–SãoPaulo/SP–CEP04543-011;or(ii)viaemail,totheelectronicaddressri@santander.com.br. Afterreceivingthedocuments,theCompany,withinthree(3)days,willinformtheShareholderregardingthereceiptofthedocumentsandtheiracceptance.Ifthesubmitteddocumentationisnotconsideredsuitable,theBallotshallbeconsideredinvalid,andtheShareholdermayregularizeitby08 /14/2026(including). RemotevotingballotsreceivedbytheCompanyafter08 /14/2026shallbedisregarded. 10 3. ATTENDANCE AT THE MEETING GeneralInformation: InaccordancewithArticle44ofCVMResolutionNo.81/22,theCentralDepositoryofB3S.A.-Brasil,Bolsa,Balcão,uponreceivingthevotinginstructionsfromtheshareholdersthroughtheirrespectivecustodyagentsshalldisregardanydiverginginstructionsirelationtothesameresolutionthathasbeenissuedbythesameCPForCNPJregistrationnumber;and Uponterminationofthedeadlineforremotevoting,inotherwords,from08/15/2026,theshareholderwillnotbeabletochangethevotinginstructionsalreadysent,exceptifattendingtheShareholders'Meetingorrepresentedbypowerofattorney,uponexpressrequestfordisregardofthevotinginstructionssentthroughtheBallot,beforetherespectivematter(s)issubjecttovoting. ADSholders HoldersofAmericanDepositaryShares(ADSs)shallbegiventherighttovoteonthematterslistedontheAgenda,subjecttothesamecriteriaappliedinrelationtonationalinvestors,accordingtothetypeofshares(commonorpreferred)onwhichtheirADSsarebacked.ADSholderswillbedulyinstructedbyTheBankofNewYorkMellon,depositoryinstitutionforADSsbackedbySantanderBrasilshares. 11 4. INFORMATION ABOUT THE AGENDA I- FIXthenumberofmembersthatwillcomposetheBoardofDirectorsoftheCompany Pursuanttotheparagraph1ofarticle14oftheCompany'sBylaws,attheGeneralMeetingwhosepurposeistoresolveontheelectionofmembersoftheBoardofDirectors,theshareholdersshallinitiallyestablishtheeffectivenumberofmembersoftheBoardofDirectorstobeelected. Inthissense,theCompany’sManagementproposesthatthenumberofmemberstocomposetheBoardofDirectorsforthetermuntiltheinvestitureofthoseelectedatthCompany'sOrdinaryGeneralMeetingof2027befixedat13(thirteen)members. II- ELECTtwo(2)newmemberstocomposetheCompany'sBoardofDirectors Aftercomplyingwiththeapplicablegovernanceapprovals,withafavorableopinionfromtheNominatingandGovernanceCommittee,theCompanyproposestotheEGMtheelectionforasupplementarytermthatwillremainineffectuntiltheinvestitureofthoseelectedattheCompany'srdinaryGeneralMeetingof2027,thefollowingcandidatesappointedbythecontrollingshareholderstocomposetheCompany'sBoardofDirectors: InformationregardingtheelectionoftheCompany'sBoardofDirectorsmembers,pursuanttoArticle11ofCVMResolution81/22,canbefoundintheManagementProposalontheCompany'sinvestorrelationswebsite(www.ri.santander.com.br),ontheCVMwebsite(www.cvm.gov.br)andontheB3website(www.b3.com.br). Name Position Daniel BarriusoRojo Director Gilson Finkelsztain Director III- Asaresultoftheresolutioninthepreviousitem,CONFIRMthecompositionoftheCompany'sBoardofDirectors. Oncethepreviousitemisapproved,theManagementproposesconfirmationofthecompositionoftheCompany'sBoardofDirectorswithatermofofficethatwillbeinforceuntiltheinvesttureofthoseelectedattheCompany's2027OrdinaryGeneralMeeting,alsotakingintoaccountthemembersoftheBoardofDirectorselectedonJuly2,2026,namely: Name Position Deborah Stern Vieitas Chairwoman (Independent) Javier Maldonado Trinchant Vice-Chairman Antonio Carlos Quintella Independent Director Cristiana Almeida Pipponzi Independent Director Cristina San Jose Brosa Director Daniel BarriusoRojo (*) Director Deborah Patricia Wright Independent Director Ede Ilson Viani Director Gilson Finkelsztain (*) Director Márcio de Andrade Schettini (*) Independent Director Oscar Rodríguez Herrero (*) Independent Director Pedro Augusto de Melo Independent Director Vanessa de Souza Lobato Barbosa Director (*) With term of office pending approval from the Brazilian Central Bank. Exhibits 13 EXHIBIT I –POWER OF ATTORNEY TEMPLATE POWER OF ATTORNEY [SHAREHOLDER],[QUALIFICATION](“Grantor”),appointsashis/her/itsattorneys-in-factMessrs.CAROLINASILVIAALVESNOGUEIRATRINDADE,Brazilian,married,registeredwithOAB/RJunderno.182.414andundertheCPF/MFunderno.124.143.167.13;andRAFAELTRIDICOFARIA,Brazilian,married,registeredwithOAB/SP358.447andundertheCPF/MFunderno.409.544.508-41,bothofthemlawyers,withcommercialaddressintheCapitalCityoftheStateofSãoPaulo,atAvenidaPresidenteJuscelinoKubitschekNos.2041-BlocoA-VilaNovaConceição(“Grantees”)torepresent,collectivelyorindividually,regardlessoftheorderofappointment,theGrantor,asshareholderofBancoSantander(Brasil)S.A.("Company"),attheCompany'sExtraordinaryGeneralMeetingtobeheld,onfirstcall,onAugust18,2026,at3:00PM,attheCompany'sprincipalplaceofbusiness,atAvenidaPresidenteJuscelinoKubitschekNo.2041-mezzanine,VilaNovaConceição,SãoPaulo/SP,andifnecessaryonsecondcall,onadatetobeinformedinduecourse,towhompowersaregrantedtoattendthemeetingandvote,onbehalfoftheGrantor,inaccordancewiththevotingguidelinessetforthbelowforeachoftheitemsontheAgenda: (a)FIXthenumberofmembersthatwillcomposetheBoardofDirectorsoftheCompany. ()Infavor()Against()Abstention (b)ELECTtwo(2)newmemberstocomposetheCompany'sBoardofDirectors. ()Infavor()Against()Abstention (c) Asaresultoftheresolutioninthepreviousitem,CONFIRMthecompositionoftheCompany'sBoardofDirectors. ()Infavor()Against()Abstention TheGranteesareherebyauthorizedtoabstainfromanyresolutionoractforwhichtheyhavenotreceived,attheirdiscretion,sufficientlyspecificvotingguidelines.TheGrantorshallholdtheGranteesaboveharmlessandfreefromanyandallclaims,disputes,demands,losses,ordamages,ofanynature,arisingfromthefulfillmentofthisinstrument,exceptincasesofactsperformedinanabusiveandexcessivemanner,pursuanttothelegislationineffect. This power of attorney shall only be valid for the Company's Extraordinary General Meeting mentioned above. [Location], [day] of [month] 2026. _____________________________________________ [Signature of the Party] 14 EXHIBIT II –RÉSUMÉ OF THE CANDIDATES Daniel BarriusoRojo Mr. Barriusois Spanish, born on 28 August 1973. He holds a degree in Computer Engineering from the Polytechnic University of Madrid (UPM), where he also served as a visiting professor in the UPM/ALI postgraduate program for ten years. He is SeniorExecutive Vice President of Banco Santander S.A., having joined Santander in 2017, after serving as Group Chief Transformation Officer and Global Head of Cybersecurity and Fraud Prevention. He has more than 29 years of experience in the banking, energy, and technology sectors, with experience at BP, Credit Suisse, and ABN AMRO, and is a member of the board of directors of Santander México, Openbank, Santander Consumer Finance, and ODS, as well as the former Chairman of Lynx Financial Tech and FS-ISAC Europe. 15 EXHIBIT II –RÉSUMÉ OF THE CANDIDATES Gilson Finkelsztain Mr. Finkelsztain is Brazilian, born on December 22, 1972. He holds a degree in Production Civil Engineering from PUC –Pontifical Catholic University of Rio de Janeiro (1994) and completed the INSEAD Advanced Management Program (2011). He served as CEO of B3 from May 2017 to June 2026. He was a member of the Board of Directors of CetipS.A. (2011–13) and its CEO (2013–17). He worked for 20 years at international financial institutions such as Citibank, JP Morgan, Bank of America Merrill Lynch, and Santander, where he held director-level positions in Brazil and abroad, always in roles related to foreign exchange, fixed income, equities, and commodities markets. He is currently CEO of Banco Santander (Brasil) S.A.