CERTIFICATION OF PERIODIC REPORT
                                  Exhibit 32.1

I, Thomas S. Kohlmann, President & Chief Executive Officer of Suffolk Bancorp
(the "Company"), certify, pursuant to Section 906 of the Sarbanes-Oxley Act of
2002, 18 U.S.C. Section 1350, that: (1) the Quarterly Report on Form 10-Q of the
Company for the quarterly period ended September 30, 2003 (the "Report") fully
complies with the requirements of Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and (2) the information
contained in the Report fairly represents, in all material respects, the
financial condition and results of operations of the Company.

Dated: November 7, 2003


/s/ Thomas S. Kohlmann
---------------------------
Thomas S. Kohlmann
President & Chief Executive Officer


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