EXHIBIT 99.3 CHIEF FINANCIAL OFFICER'S CERTIFICATION REQUIRED UNDER SECTION 906 OF SARBANES-OXLEY ACT OF 2002 In connection with the quarterly report of TIB Financial Corp. (the "Company") on Form 10-Q for the period ended March 31, 2003, as filed with the Securities and Exchange Commission (the "Report"), I, David P. Johnson, Executive Vice President and Chief Financial Officer of the Company, certify pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that this Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that, to my knowledge, the information contained in the Report fairly presents, in all material respects, the financial condition and results of operation of the Company. Date: May 9, 2003 /s/ David P. Johnson -------------- -------------------------------------------- David P. Johnson Executive Vice President and Chief Financial Officer 23