(Mark One) For the quarterly period ended June30, 2026- OR - TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period fromtoCommission file number 001-31553 CME GROUP INC. (Exact name of registrant as specified in its charter) Securities registered pursuant to Section 12(b) of the Act: 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 submittedpursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that theregistrant was 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, a smallerreporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smallerreporting company” and "emerging growth company" in Rule 12b-2 of the Exchange Act. 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). The number of shares outstanding of each of the registrant’s classes of common stock as of July8, 2026 was as follows: 359,576,125shares of ClassA common stock, $0.01 par value; 625 shares of Class B-1 common stock, $0.01 par value; 813 shares of Class B-2common stock, $0.01 par value; 1,287 shares of Class B-3 common stock, $0.01 par value; and 413 shares of Class B-4 commonstock, $0.01 par value. Table of Contents CME GROUP INC.FORM 10-QINDEX PART I. FINANCIAL INFORMATION Item1.Financial Statements5Consolidated Balance Sheets at June 30, 2026 and December 31, 20255Consolidated Statements of Income for the Quarters and Six Months Ended June 30, 2026 and 20256Consolidated Statements of Comprehensive Income for the Quarters and Six Months Ended June 30, 2026 and 20257Consolidated Statements of Equity for the Quarters and Six Months Ended June 30, 2026 and 20258Consolidated Statements of Cash Flows for the Six Months Ended June 30, 2026 and 202510Notes to Unaudited Consolidated Financial Statements12Item2.Management’s Discussion and Analysis of Financial Condition and Results of Operations23Item3.Quantitative and Qualitative Disclosures About Market Risk32Item4.Controls and Procedures32PART II. OTHER INFORMATION32Item1.Legal Proceedings32Item1A.Risk Factors32Item2.Unregistered Sales of Equity Securities and Use of Proceeds33Item 5.Other Information33Item6.Exhibits34SIGNATURES35 PART I. FINANCIAL INFORMATION Certain Terms All references to “options” or “options contracts” in the text of this document refer to options on futures contracts.Further information about CME Group and its products can be found at http://www.cmegroup.com. Information made available on ourwebsite does not constitute a part of this Quarterly Report on Form 10-Q. Information about Contract Volume and Average Rate per Contract Unless otherwise noted, all amounts regarding contract volume and average rate per contract are for CME Group's listed futures andoptions on futures contracts and exclude CME Group's event contracts. Trademark Information CME Group, the Globe logo, CME, Chicago Mercantile Exchange, Globex, and E-mini are trademarks of Chicago MercantileExchange Inc. (CME), CBOT and Chicago Board of Trade are trademarks of Board of Trade of the City of Chicago, Inc.NYMEX,New York Mercantile Exchange and ClearPort are trademarks of New York Mercantile Exchange, Inc.COMEX is a trademark ofCommodity Exchange, Inc. BrokerTec is a trademark of BrokerTec Americas LLC and EBS is a trademark of EBS Group Limited.Dow Jones, Dow Jones Industrial Average, S&P 500 and S&P are service and/or trademarks of Dow Jones Trademark Holdings LLC,Standard & Poor's Financial Services LLC and S&P Dow Jones Indices LLC, as the case may be, and have been licensed for use byCME. All other trademarks are the property of their respective owners. Forward-Looking Statements From time to time, in this Quarterly Report on Form 10-Q as well as in other written reports and verbal statements, we discuss ourexpectations regarding future performance. These forward-looking statements are identified by their use of terms and phrases such as“believe,” “anticipate,” “could,” “estimate,” “intend,” “may,” “plan,” “expect” and similar expressions, including references toas