AUTOMATIC DATA PROCESSING INC 10-Q

Item 5. Other Information During the fiscal quarter ended September 30, 2025, our executive officers and directors adopted the following trading arrangements that are intended to satisfy the affirmative defense of Rule 10b5-1(c). Name & Title Date of Adoption Duration of Trading Arrangement The maximum number of securities to be sold pursuant to the trading arrangement (1) Maria Black , President and Chief Executive Officer September 4, 2025 January 2, 2026 – December 31, 2026 57,214 Michael Bonarti , Chief Administrative Officer September 4, 2025 February 3, 2026 – December 31, 2026 20,805 Christopher D’Ambrosio , Chief Strategy Officer September 8, 2025 January 2, 2026 – December 31, 2026 6,202 Joseph DeSilva , Executive Vice President, North America and Chief of Operations September 4, 2025 January 2, 2026 – December 31, 2026 14,225 David Foskett , President, Global Sales September 8, 2025 February 5, 2026 – December 31, 2026 3,054 Peter Hadley , Chief Financial Officer September 4, 2025 January 2, 2026 – December 31, 2026 1,487 Sreeni Kutam , President, Global Product and Innovation September 4, 2025 January 2, 2026 – December 31, 2026 13,364 David Kwon , Chief Legal Officer/General Counsel September 4, 2025 January 2, 2026 – December 31, 2026 5,116 Jonathan Lehberger , Corporate Controller September 4, 2025 January 2, 2026 – December 31, 2026 2,545 Virginia Magliulo , Executive Vice President, Employer Services International September 8, 2025 January 12, 2026 – December 31, 2026 5,235 Brian Michaud , Executive Vice President, Smart Compliance Solutions & Human Resources Outsourcing September 9, 2025 January 2, 2026 – December 31, 2026 10,785 Carlos Rodriguez , Director September 4, 2025 September 4, 2025 January 6, 2026 – June 30, 2026 September 2, 2026 – December 31, 2026 13,813 (2) 24,651 (1) Securities reported in this column reflect options, restricted stock units (“RSUs”), performance-based stock units (“PSUs”) and shares of common stock, as appropriate. In the case of RSUs, quantities included in this column reflect the full amount of RSUs as reported in an officer’s respective plan and do not reflect the impact of tax withholding which will not be determined until the RSUs vest. In the case of PSUs (which have a three-year performance period), quantities included in this column reflect the application of performance factors at target and the inclusion of accrued dividend equivalents through the date of adoption of the trading arrangement. The PSU amounts do not reflect the impact of tax withholding which will not be determined until the PSUs vest. In addition, securities reported in this column include securities subject to limit orders and such orders may not fill if limit order conditions are not met. (2) Indirect shares held by trust. 41 Item 6. Exhibits Exhibit Number Exhibit 31.1 Certification by Maria Black pursuant to Rule 13a-14(a) of the Securities Exchange Act of 1934 31.2 Certification by Peter Hadley pursuant to Rule 13a-14(a) of the Securities Exchange Act of 1934 32.1 Certification by Maria Black pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 32.2 Certification by Peter Hadley pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002 101.INS Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document 101.SCH Inline XBRL Taxonomy Extension Schema 101.CAL Inline XBRL Taxonomy Extension Calculation Linkbase 101.LAB Inline XBRL Taxonomy Label Linkbase 101.PRE Inline XBRL Taxonomy Extension Presentation Linkbase 101.DEF Inline XBRL Taxonomy Extension Definition Document 104 Cover Page Interactive Data File - the cover page interactive data file does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document 42 SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. AUTOMATIC DATA PROCESSING, INC. (Registrant) Date: October 31, 2025 /s/ Peter Hadley Peter Hadley Chief Financial Officer (Title) 43