Company: WTFCN
Filing Date: 2025-05-09
Form Type: 424B5
Source: 0001104659-25-046769
Chunk: 9

Company: WINTRUST FINANCIAL CORP
Filing Date: 2025-05-09
Form: 424B5
Chunk 9
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ilities and pandemics), and the effects of climate change.

There can be no assurances that future actual results will correspond to these forward-looking statements. You are cautioned not to place undue reliance on any forward-looking statement made by us or on our behalf. Any such statement speaks only as of the date the statement was made or as of such date that may be referenced within the statement. We undertake no obligation to update any forward-looking statements or reflect the impact of circumstances or events that arise after the date the forward-looking statement was made. You are advised, however, to consult further disclosures management makes on related subjects in Wintrust’s reports filed with the SEC.

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TABLE OF CONTENTS

### SUMMARY
This summary highlights selected information from this prospectus supplement and does not contain all of the information that you should consider in making your investment decision. You should read this summary together with the more detailed information appearing elsewhere in this prospectus supplement as well as the information in the accompanying prospectus and in the documents incorporated by reference or deemed incorporated by reference into this prospectus supplement and the accompanying prospectus. You should carefully consider, among other things, the matters discussed in the sections titled “Risk Factors” in this prospectus supplement and in our Annual Report on Form 10-K for the year ended December 31, 2024. In addition, certain statements include forward-looking information that involves risks and uncertainties. See “Special Note Concerning Forward-Looking Statements” in this prospectus supplement.

### Wintrust Financial Corporation
Wintrust Financial Corporation, an Illinois corporation, which was incorporated in 1992, is a financial holding company based in Rosemont, Illinois, with total assets of approximately $65.9 billion as of March 31, 2025. We provide community-oriented, personal and commercial banking services to customers generally located in the Chicago metropolitan area, southern Wisconsin, northwest Indiana and west Michigan (“our market area”) through our sixteen wholly-owned-banking subsidiaries (collectively, the “banks”), as well as the origination of residential mortgages for sale into the secondary market through Wintrust Mortgage, a division of Barrington Bank & Trust Company, N.A. In addition, we provide specialty finance services, including financing for the payment of property and casualty insurance premiums and life insurance premiums on a national basis through FIRST Insurance Funding, a division of our wholly-owned subsidiary Lake Forest Bank & Trust Company, N.A. (“Lake Forest Bank”), and Wintrust Life Finance, a division of Lake Forest