Exhibit 99.1



The  following  certification  is provided by the  undersigned  Chief  Executive
Officer  of  Wintrust  Financial  Corporation  on the  basis  of such  officer's
knowledge  and belief for the sole purpose of complying  with 18 U.S.C.  Section
1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.

                                  CERTIFICATION
                                  -------------


In connection with the Quarterly Report of Wintrust  Financial  Corporation (the
"Company")  on Form 10-Q for the period ended  September  30, 2002 as filed with
the Securities and Exchange Commission on November 12, 2002, (the "Report"),  I,
Edward J. Wehmer,  President and Chief Executive Officer of the Company,  hereby
certify,  pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 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, as amended; 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/  EDWARD J. WEHMER
                                   ---------------------------------------------
                                    Name:  Edward J. Wehmer
                                   Title:  President and Chief Executive Officer
                                    Date:  November 12, 2002