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): September 17, 1999


                         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 5.  OTHER EVENTS.

On September 17, 1999, Wintrust Financial Corporation  ("Wintrust" or "Company")
announced the signing of an agreement to acquire  Milwaukee-based  Tricom,  Inc.
("Tricom"),  a  financial  and  administrative  service  bureau to the  staffing
industry.  Tricom has been in  business  for ten years and  provides  short-term
accounts  receivable  financing  and  value-added   out-sourced   administrative
services, such as data processing of payrolls, billing and bookkeeping services,
to temporary staffing service clients located throughout the United States. This
proposed  acquisition,  by virtue of the funding  resources  of  Wintrust,  will
provide  Tricom with  additional  capital  necessary to expand its financing and
administrative  services  in  a  national  market.  The  Tricom  acquisition  is
consistent with the Company's stated strategy of adding a variety of diversified
earning  asset and  fee-based  business  niches to augment  its  community-based
banking revenues.

Under the terms of the agreement to acquire 100% of Tricom's  common stock,  the
purchase price is comprised of part cash and part stock,  including the issuance
of  approximately  228,000 shares of Wintrust Common Stock. The transaction will
be recorded using the purchase  method of  accounting,  is subject to regulatory
approval, and is expected to close in October 1999.


ITEM 7.  FINANCIAL STATEMENTS AND EXHIBITS.

(c)      Exhibit

September  17, 1999 Press  Release - Wintrust  Financial  Corporation  Announces
Plans to Acquire Tricom, Inc.

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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)


Date:  September 29, 1999                              /s/ David A. Dykstra
                                                       Executive Vice President
                                                       & Chief Financial Officer


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