Company: UMBFO
Filing Date: 2025-04-11
Form Type: S-3ASR
Source: 0001193125-25-079117
Chunk: 1

Company: UMB FINANCIAL CORP
Filing Date: 2025-04-11
Form: S-3ASR
Chunk 1
---
 filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. ☐ Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-acceleratedfiler, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2of the Exchange Act.

| Large accelerated filer |     | ☒ |     | Accelerated filer         |     | ☐ |
| Non-accelerated filer   |     | ☐ |     | Smaller reporting company |     | ☐ |
|                         |     |   |     | Emerging growth company   |     | ☐ |

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act. ☐

PROSPECTUS UMB Financial Corporation Common Stock, Preferred Stock, Depositary Shares, Warrants, Stock Purchase Contracts, Stock Purchase Units and Debt Securities We may offer, from time to time, in one or more offerings, together or separately, in one or more series or classes and in amounts, at prices and on terms that we will determine at the time of offering:

| • |     | shares of common stock; |

| • |     | shares of preferred stock; |

| • |     | depositary shares; |

| • |     | warrants; |

| • |     | stock purchase contracts; |

| • |     | stock purchase units; or |

| • |     | debt securities, which may be either senior debt securities or subordinated debt securities. |

We refer to the common stock, preferred stock, depositary shares, warrants, stock purchase contracts, stock purchase units and debt securities collectively as the “securities” in this prospectus. This prospectus describes some of the general terms that may apply to these securities and the general manner in which they may be offered. We will provide the specific terms of these securities in prospectus supplements. You should read this prospectus, the applicable prospectus supplement and any “free writing prospectus” carefully before you invest. The securities may be offered and sold directly