Essendant (ESND) 10-Q 2012 Q3 Quarterly report

Exhibit 32.1

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 Quarterly Report of United Stationers Inc. (the “Company”) on Form 10-Q for the quarterly period ended September 30, 2012, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), P. Cody Phipps, Chief Executive Officer of the Company, and Fareed A. Khan, Senior Vice President and Chief Financial Officer of the Company, each hereby 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 result of operations of the Company.

A signed original of this written statement required by Section 906 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

/s/ P. Cody Phipps

P. Cody Phipps

President and Chief Executive Officer

October 30, 2012

/s/ Fareed A. Khan

Fareed A. Khan

Senior Vice President and Chief Financial Officer

October 30, 2012