Company: WTFCN
Filing Date: 2025-05-09
Form Type: 424B5
Source: 0001104659-25-046769
Chunk: 64

Company: WINTRUST FINANCIAL CORP
Filing Date: 2025-05-09
Form: 424B5
Chunk 64
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 to a refund, provided that the holder furnishes the required information to the IRS.

#### Foreign Account Tax Compliance Act (“FATCA”)
FATCA generally imposes a 30% withholding tax on (i) payments of dividends on depositary shares and (ii) subject to the proposed Treasury regulations discussed below, the gross proceeds from the sale

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or other disposition of depositary shares that produce U.S. source dividends (including the sale, exchange, redemption, retirement or other disposition of the depositary shares), in each case to certain foreign financial institutions and certain other non-U.S. entities unless certain certification, information reporting and other specified requirements satisfied. An inter-governmental agreement between the United States and an applicable non-U.S. country may modify such requirements.

Treasury regulations proposed in December 2018 eliminate FATCA withholding on the gross proceeds from a sale or other disposition of instruments, such as the depositary shares, that produce U.S. source dividends. In its preamble to such proposed Treasury regulations, the IRS stated that taxpayers may generally rely on the proposed Treasury regulations until final Treasury regulations are issued. Under certain circumstances, a non-U.S. holder might be eligible for refunds or credits of such taxes. Prospective investors should consult their own tax advisors regarding the relevant U.S. law and other official guidance on FATCA withholding.

You are urged to consult your own tax advisors regarding FATCA and the application of these requirements to your investment in the depositary shares.

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UNDERWRITING We are offering the depositary shares described in this prospectus supplement through a number of underwriters. We have entered into an underwriting agreement with the underwriters named below. Subject to the terms and conditions of the underwriting agreement, we have agreed to sell to the underwriters, and each underwriter has severally agreed to purchase, at the public offering price less the underwriting discounts set forth on the cover page of this prospectus supplement, the number of depositary shares listed next to its name below:

| Name                           | ​ | ​ | Number ofDepositary Shares |   |            |   | ​ |
| RBC Capital Markets, LLC       | ​ | ​ | ​                          | ​ | 10,625,000 | ​ | ​ |
| Keefe, Bruyette & Woods, Inc.  | ​ | ​ | ​                          | ​ |