Form 10-Q ☒Quarterly Report Pursuant to Section13 or 15(d) of the Securities Exchange Act of 1934For the quarterly period ended:March 31, 2026Or Transition Report Pursuant to Section13 or 15(d) of the Securities Exchange Act of 1934For the transition period from ________________ to ________________Commission file number:001-13221 Cullen/Frost Bankers, Inc. (Exact name of registrant as specified in its charter) Texas74-1751768(State or other jurisdiction of incorporation or organization)(I.R.S. Employer Identification No.) 111 W. Houston Street,San Antonio,Texas(Address of principal executive offices) (210)220-4011 (Registrant's telephone number, including area code) N/A(Former name, former address and former fiscal year, if changed since last report Securities registered pursuant to Section12(b) of the Act: Title of each classTradingSymbol(s)Name of each exchange onwhich registered Common Stock, $.01 Par Value Depositary Shares, each representing a 1/40th interest in a share of4.450% Non-Cumulative Perpetual Preferred Stock, Series B CFR.PrBNew York Stock Exchange Indicate by check mark whether the registrant: (1)has filed all reports required to be filed by Section13 or 15(d) of the SecuritiesExchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),and (2)has been subject to such filing requirements for the past 90 days.Yes☒No☐ Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuantto Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrantwas required to submit such files).Yes☒No☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reportingcompany, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reportingcompany,” and “emerging growth company” in Rule 12b-2 of the Exchange Act. Large accelerated filer☒Acceleratedfiler☐Non-accelerated filer☐Smallerreportingcompany☐Emerging growth company☐ If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period forcomplying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.☐ Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).Yes☐No☒As of April27, 2026, there were 62,797,048 shares of the registrant’s Common Stock, $.01 par value, outstanding. Cullen/Frost Bankers, Inc.Quarterly Report on Form 10-QMarch31, 2026 Table of Contents Part I - Financial Information Item1.Financial Statements (Unaudited)Consolidated Balance SheetsConsolidated Statements of IncomeConsolidated Statements of Comprehensive IncomeConsolidated Statements of Changes in Shareholders’ EquityConsolidated Statements of Cash FlowsNotes to Consolidated Financial StatementsItem2.Management's Discussion and Analysis of Financial Condition and Results of OperationsItem3.Quantitative and Qualitative Disclosures About Market RiskItem4.Controls and Procedures Part II - Other InformationItem1.Legal Proceedings Item1A.Risk FactorsItem2.Unregistered Sales of Equity Securities, Use of Proceeds, and Issuer Purchases of Equity SecuritiesItem3.Defaults Upon Senior SecuritiesItem4.Mine Safety DisclosuresItem5.Other InformationItem6.Exhibits Signatures Item1. Financial Statements (Unaudited)Cullen/Frost Bankers, Inc.Consolidated Balance Sheets(Dollars in thousands, except per share amounts) Cullen/Frost Bankers, Inc.Consolidated Statements of Income(Dollars in thousands, except per share amounts) Table of Contents Cullen/Frost Bankers, Inc.Consolidated Statements of Comprehensive Income(Dollars in thousands) (Dollars in thousands, except per share amounts) Cullen/Frost Bankers, Inc.Consolidated Statements of Cash Flows(Dollars in thousands) Table of Contents Notes to Consolidated Financial Statements(Table amounts in thousands, except for share and per share amounts) Note 1 - Significant Accounting Policies Nature of Operations.Cullen/Frost Bankers, Inc. (“Cullen/Frost”) is a financial holding company and a bank holding companyheadquartered in San Antonio, Texas that provides, through its subsidiaries, a broad array of products and services throughout numerousTexas markets. The terms “Cullen/Frost,” “the Corporation,” “we,” “us,” and “our” mean Cullen/Frost Bankers, Inc., and its subsidiaries,when appropriate. In addition to general commercial and consumer banking, other products and services offered include trust andinvestment management, insurance, brokerage, mutual funds, leasing, treasury management, capital markets advisory, and itemprocessing. Basis of Presentation.The consolidated financial statements in this Quarterly Re