Company: WTFCN
Filing Date: 2025-05-09
Form Type: 424B5
Source: 0001104659-25-046769
Chunk: 29

Company: WINTRUST FINANCIAL CORP
Filing Date: 2025-05-09
Form: 424B5
Chunk 29
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, and the banking system as a whole, and not for the protection of our security holders. A change in applicable statutes, regulations or regulatory policy may have a material adverse effect on our business, financial condition (including capital adequacy) and results of operations.

#### Regulatory Capital Treatment
We are required by the Federal Reserve to maintain certain levels of consolidated capital for regulatory purposes. Under applicable Federal Reserve capital regulations, the Preferred Stock will be treated as additional Tier 1 capital of Wintrust Financial Corporation.

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TABLE OF CONTENTS

### DESCRIPTION OF PREFERRED STOCK
You should read the following description of the Preferred Stock along with the “Description of Capital Stock — Preferred Stock” beginning on page 15of the accompanying prospectus. This description of the Preferred Stock is qualified by the Certificate of Designations relating to the Preferred Stock (the “Certificate of Designations”), and where this description is inconsistent with the description of the Preferred Stock contained in the accompanying prospectus or the description of the Preferred Stock in the Certificate of Designations, the Certificate of Designations will control. The following summary of the terms and provisions of the Preferred Stock does not purport to be complete and is qualified in its entirety by reference to the pertinent sections of our amended and restated articles of incorporation, as amended, which we refer to as our Articles of Incorporation, including the Certificate of Designations, which will be filed as an exhibit to a Current Report on Form 8-K and incorporated by reference into this prospectus supplement, the accompanying prospectus and the registration statement of which they form a part, and the applicable provisions of the Illinois Business Corporation Act, as amended, and federal law governing bank holding companies. As used in this section, the terms “Wintrust,” “we,” “us,” or “our” refer to Wintrust Financial Corporation and not any of its subsidiaries.

#### General
The depositary will be the sole holder of the Preferred Stock, as described under “Description of Depositary Shares” below, and all references in this prospectus supplement to the holders of the Preferred Stock shall mean the depositary. However, the holders of depositary shares will be entitled, through the depositary, to exercise the rights and preferences of the holder of the Preferred Stock, as described under “Description of Depositary Shares.”

The Preferred Stock is a single series of our authorized preferred stock consisting of 18,000 shares. Shares of the Preferred Stock will rank (i) senior to our common stock and each other