UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K

                 CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d)
                     OF THE SECURITIES EXCHANGE ACT OF 1934

        Date of Report (Date of Earliest Event Reported): October 1, 2003


                         WINTRUST FINANCIAL CORPORATION
             (Exact Name of Registrant as Specified in its Charter)


                         Commission File Number 0-21923


            Illinois                                  36-3873352
-----------------------------------      -----------------------------------
    (State or other Jurisdiction         (I.R.S. Employer Identification No.)
        of Incorporation)



                               727 North Bank Lane
                           Lake Forest, Illinois 60045
            -------------------------------------------------------
                    (Address of Principal Executive Offices)



                                 (847) 615-4096
             -------------------------------------------------------
              (Registrant's Telephone Number, Including Area Code)





ITEM 9.  REGULATION FD DISCLOSURE.
         -------------------------

         On October 1, 2003, Wintrust Financial Corporation (the "Company")
announced the completion of its previously announced pending acquisition of 100%
of the ownership interest of Advantage National Bancorp, Inc. ("Advantage") in a
stock merger transaction. Advantage is the parent company of Advantage National
Bank that has locations in Elk Grove Village and Roselle, Illinois. Attached as
Exhibit 99.1 is a copy of the press release relating to the announcement, which
is incorporated herein by reference.

         Note: the information in this report (including the exhibits) is
furnished pursuant to Item 9 and shall not be deemed to be "filed" for the
purposes of Section 18 of the Securities Exchange Act of 1934 or otherwise
subject to the liabilities of that section, or incorporated by reference in any
filing under the Securities Act of 1933, as amended, or the Exchange Act, except
as shall be expressly set forth by specific reference in such a filing. This
report will not be deemed a determination or an admission as to the materiality
of any information in the report that is required to be disclosed solely by
Regulation FD.


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                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.



                         WINTRUST FINANCIAL CORPORATION
                                  (Registrant)





                                                  /s/ David L. Stoehr
Date:  October 1, 2003                            ------------------------------
                                                  David L. Stoehr
                                                  Executive Vice President &
                                                    Chief Financial Officer


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                                INDEX TO EXHIBITS
                                -----------------

Exhibit
-------

99.1              Press release dated October 1, 2003.



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