MARKETAXESS HOLDINGS INC

Our management, including the Chief Executive Officer and Interim Chief Financial Officer, evaluated the effectiveness of our “disclosure controls and procedures,” as that term is defined in Rule 13a-15(e) and Rule 15d-15(e) promulgated under the Exchange Act, as of December 31, 2023. Based on that evaluation, the Chief Executive Officer and Interim Chief Financial Officer concluded that the disclosure controls and procedures are effective to ensure that information required to be disclosed by MarketAxess in the reports that we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms, and to ensure that information is accumulated and communicated to our management, including the Chief Executive Officer and Interim Chief Financial Officer, as appropriate to allow timely decisions regarding required disclosure.

There were no changes in our internal control over financial reporting (as defined in Rule 13a-15(f) and Rule 15d-15(f) under the Exchange Act) during the quarter ended December 31, 2023 identified in connection with the evaluation thereof by our management, including the Chief Executive Officer and Interim Chief Financial Officer, that materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Management’s annual report on internal control over financial reporting and the report of our independent registered public accounting firm appears in Part II, Item 8. Financial Statements and Supplementary Data of this Annual Report on Form 10-K.