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adp-202601281/28/20260000008670FALSE00000086702026-01-282026-01-28

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 28, 2026

Automatic Data Processing, Inc.

(Exact name of registrant as specified in charter)

Delaware1-539722-1467904 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.)

One ADP Boulevard, Roseland, New Jersey                07068 (Address of principal executive offices)                 (Zip Code)

(973) 974-5000 (Registrant's telephone number, including area code) N/A (Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act: Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, $0.10 Par Value (voting)ADPNASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 2.02. Results of Operations and Financial Condition.

On January 28, 2026, the Registrant issued a press release announcing that the Registrant's financial results for the second quarter ended December 31, 2025 were available through an earnings release available on the Registrant's website. A copy of the Registrant's earnings release is attached hereto as Exhibit 99 and is hereby incorporated by reference.

Item 9.01. Financial Statements and Exhibits. (d)Exhibit 99 Earnings Release dated January 28, 2026 issued by Automatic Data Processing, Inc.

104Cover Page Interactive Data File, embedded in Inline XBRL.

SIGNATURE

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 hereunto duly authorized.

AUTOMATIC DATA PROCESSING, INC.

(Registrant)

By:/s/ Peter Hadley Date: January 28, 2026Name: Peter Hadley Title: Chief Financial Officer

3

Exhibit Index

Exhibit NumberDescription 99 Earnings Release dated January 28, 2026 issued by Automatic Data Processing, Inc.

104Cover Page Interactive Data File, embedded in Inline XBRL.

4

adp-2025102910/29/20250000008670FALSE00000086702025-10-292025-10-29

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 29, 2025

Automatic Data Processing, Inc.

(Exact name of registrant as specified in charter)

Delaware1-539722-1467904 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS Employer Identification No.)

One ADP Boulevard, Roseland, New Jersey                07068 (Address of principal executive offices)                 (Zip Code)

(973) 974-5000 (Registrant's telephone number, including area code) N/A (Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: ☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act: Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, $0.10 Par Value (voting)ADPNASDAQ Global Select Market

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter). Emerging growth company☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Item 2.02. Results of Operations and Financial Condition.

On October 29, 2025, the Registrant issued a press release announcing that the Registrant's financial results for the first quarter ended September 30, 2025 were available through an earnings release available on the Registrant's website. A copy of the Registrant's earnings release is attached hereto as Exhibit 99 and is hereby incorporated by reference.

Item 9.01. Financial Statements and Exhibits. (d)Exhibit 99 Earnings Release dated October 29, 2025 issued by Automatic Data Processing, Inc.

104Cover Page Interactive Data File, embedded in Inline XBRL.

SIGNATURE

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 hereunto duly authorized.

AUTOMATIC DATA PROCESSING, INC.

(Registrant)

By:/s/ Peter Hadley Date: October 29, 2025Name: Peter Hadley Title: Chief Financial Officer

3

Exhibit Index

Exhibit NumberDescription 99 Earnings Release dated October 29, 2025 issued by Automatic Data Processing, Inc.

104Cover Page Interactive Data File, embedded in Inline XBRL.

4