EXHIBIT 32.2

CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Annual Report of Automatic Data Processing, Inc. (the “Company”) on Form 10-K for the fiscal year ending June 30, 2015 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Jan Siegmund, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

/s/ Jan Siegmund

Jan Siegmund

Chief Financial Officer

Date: August 7, 2015