Company: THS
Filing Date: 2025-03-13
Form Type: DEFA14A
Source: 0001320695-25-000031
Chunk: 0

Company: TreeHouse Foods, Inc.
Filing Date: 2025-03-13
Form: DEFA14A
Chunk 0
---
### UNITED STATES

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549
<div align='center'>(Rule 14a-101)</div>

#### SCHEDULE 14A INFORMATION
<div align='center'>Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No.__ )</div>

| ☒ |     | Filed by the Registrant |     | ☐ |     | Filed by a Party other than the Registrant |

| CHECK THE APPROPRIATE BOX: |     |                                                                                 |
| ☐                          |     | Preliminary Proxy Statement                                                     |
| ☐                          |     | Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) |
| ☐                          |     | Definitive Proxy Statement                                                      |
| ☒                          |     | Definitive Additional Materials                                                 |
| ☐                          |     | Soliciting Material Under §240.14a-12                                           |

#### TREEHOUSE FOODS, INC.
<div align='center'>(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)</div>

| PAYMENT OF FILING FEE (CHECK ALL BOXES THAT APPLY): |     |                                                                                                     |
| ☒                                                   |     | No fee required                                                                                     |
| ☐                                                   |     | Fee paid previously with preliminary materials                                                      |
| ☐                                                   |     | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11 |