Company: AOS
Filing Date: 2025-03-12
Form Type: DEFA14A
Source: 0000091142-25-000049
Chunk: 0

Company: SMITH A O CORP
Filing Date: 2025-03-12
Form: DEFA14A
Chunk 0
---
### UNITED

### STATES

### SECURITIES

#### AND

### EXCHANGE

### COMMISSION

#### Washington,

#### D.C.

#### 20549

### SCHEDULE

#### 14A

#### Proxy

#### Statement

#### Pursuant

#### to

#### Section

#### 14(a)

#### of

#### The

#### Securities Exchange Act of 1934
<div align='center'>(Amendment</div>

#### No.
#### )

Filed by the Registrant ☒ Filed by a party other than the Registrant ☐

Check the appropriate box:

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

#### A. O. Smith Corporation
<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 the appropriate box):

| ☒ |     | 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 |

<div align='center'>SUPPLEMENT TO PROXY STATEMENT FOR 2025 ANNUAL MEETING OF STOCKHOLDERS</div>

This supplement (“Supplement”) relates to the Notice of Annual Meeting of Stockholders and Proxy Statement (the “Proxy Statement”) that A. O. Smith Corporation (“we,” "us" or the “Company”) filed with the Securities and Exchange Commission (the “SEC”) on February 27, 2025, and furnished to our stockholders in connection with the solicitation of proxies by our Board of Directors (the “Board”) for the Company’s 2025 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on April 8, 2025, or at any adjournment thereof.

The purpose of this Supplement is to provide updated information relating to Adrian I. Peace, who was one of the nominees for election by holders of Common Stock