Company: SOJE
Filing Date: 2025-11-04
Form Type: 424B2
Source: 0000092122-25-000092
Chunk: 4

Company: SOUTHERN CO
Filing Date: 2025-11-04
Form: 424B2
Chunk 4
---
 |     |  1 |
| Risk Factors                                                             |     |  1 |
| Available Information                                                    |     |  1 |
| Incorporation of Certain Documents by Reference                          |     |  1 |
| The Southern Company                                                     |     |  2 |
| Use of Proceeds                                                          |     |  2 |
| Description of the Common Stock                                          |     |  2 |
| Description of the Senior Notes                                          |     |  2 |
| Description of the Junior Subordinated Notes                             |     |  5 |
| Description of the Stock Purchase Contracts and the Stock Purchase Units |     | 10 |
| Plan of Distribution                                                     |     | 10 |
| Legal Matters                                                            |     | 11 |
| Experts                                                                  |     | 11 |

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### ABOUT THIS PROSPECTUS SUPPLEMENT
This Prospectus Supplement and the accompanying Prospectus contain information about the Company and the Equity Units offered hereby. This Prospectus Supplement and the accompanying Prospectus also refer to information contained in other documents that the Company files with the Securities and Exchange Commission (the “SEC”). To the extent the information in this Prospectus Supplement is inconsistent with information in the Prospectus, you should rely on this Prospectus Supplement.

It is important for you to read and consider all of the information contained in this Prospectus Supplement, the accompanying Prospectus and the documents incorporated by reference herein in making your investment decision. You should also read and consider the information in the documents the Company referred you to in “Available Information” and “Incorporation of Certain Documents by Reference” in this Prospectus Supplement.

The Company has included cross-references in this Prospectus Supplement and the accompanying Prospectus to captions in these materials where you can find additional related discussions. The table of contents in this Prospectus Supplement provides the pages on which these captions are located.

### AVAILABLE INFORMATION
The Company is subject to the informational requirements of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and in accordance with the Exchange Act files reports, proxy statements and other information with the SEC. The SEC maintains a website that contains reports, proxy and information statements and other information regarding registrants including the Company that file electronically at http://www.sec.gov. Only the Company’s SEC filings referenced below are incorporated by reference herein.

### INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
The following documents have been filed with the SEC pursuant to the Exchange Act, and