Exhibit 32.1

CF INDUSTRIES HOLDINGS, INC.

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 on Form 10-Q of CF Industries Holdings, Inc. (the Company) for the quarterly period ended March 31, 2007 as filed with the Securities and Exchange Commission on the date hereof (the Report), I, Stephen R. Wilson, as President and Chief Executive Officer of the Company, hereby certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that, to the best of my knowledge:

(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/ STEPHEN R. WILSON
Stephen R. Wilson
President and Chief Executive Officer, Chairman of the Board
(Principal Executive Officer)
Date: May 4, 2007