Exhibit 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

We consent to the incorporation by reference in this Registration Statement on Form S-3 of our reports dated August 7, 2024, relating to the financial statements of Automatic Data Processing, Inc., and the effectiveness of Automatic Data Processing, Inc.’s internal control over financial reporting, appearing in the Annual Report on Form 10-K of Automatic Data Processing, Inc. for the year ended June 30, 2024. We also consent to the reference to us under the heading “Experts” in such Registration Statement.

/s/ Deloitte & Touche LLP

Morristown, New Jersey

September 4, 2024