| Southern Ionics Incorporated TX | Manufacturing | 0 | — | A |
| Southern Iowa Electric Cooperative IA | Utilities | 0 | — | A |
| Southern Kern Unified School District CA | Educational Services | 12 | $84,827 | — |
| Southern Kidney Specialists, PLC TN | Healthcare & Social Assistance | 1 | $250,000 | — |
| Southern Lakes Plumbing and Heating, Inc. WI | Construction | 0 | — | F |
| Southern Lifting and Hoisting LLC TX | Manufacturing | 0 | — | B |
| Southern Light Farm TN | Agriculture & Forestry | 0 | — | A |
| Southern Living Contractors, Inc FL | Construction | 0 | — | F |
| Southern Lumber and Millwork SC | Retail Trade | 0 | — | C |
| Southern Lumber Supply AL | Retail Trade | 0 | — | A |
| Southern Lure Company MS | — | 0 | — | — |
| Southern Machine & Fabrication Co., Inc. GA | Manufacturing | 0 | — | F |
| Southern Machine Works, Inc. OK | Manufacturing | 0 | — | A |
| Southern Machinery Repair, Inc. TN | Other Services | 0 | — | F |
| Southern Maine Health Care ME | Healthcare & Social Assistance | 0 | — | F |
| Southern Management Companies VA | Real Estate | 0 | — | F |
| Southern Manufacturing Technologies, Inc. FL | Manufacturing | 0 | — | A |
| Southern Market Group Inc. OK | Retail Trade | 0 | — | F |
| Southern Maryland Electric Cooperative MD | Utilities | 0 | — | F |
| Southern Mechanical LLC dba Energy-One RI | Construction | 0 | — | F |
| Southern Mechanical LLC dba H&H Mechanical FL | Construction | 0 | — | D |
| Southern Mechanical Services Inc. NC | Construction | 0 | — | F |
| Southern Mechanical, Inc. MD | Construction | 0 | — | A |
| Southern Mechanical, LLC. TN | Construction | 0 | — | F |
| Southern Medical Partners, L.L.C. LA | Administrative & Waste Services | 1 | $239,200 | — |
| Southern MEP, Inc SC | Construction | 0 | — | A |
| Southern Metal Fabricators, Inc. AL | Manufacturing | 0 | — | F |
| Southern Metal Products Co Inc. KY | Manufacturing | 0 | — | A |
| Southern Metalcraft GA | Manufacturing | 0 | — | F |
| Southern Metals Recycling GA | Wholesale Trade | 0 | — | B |
| SOUTHERN METHODIST UNIVERSITY TX | Educational Services | 19 | $68,629 | — |
| Southern Milling & Lumber Inc FL | Manufacturing | 0 | — | F |
| Southern Minnesota Beet Sugar Cooperative MN | Manufacturing | 0 | — | F |
| Southern Minnesota Education Consortium MN | Educational Services | 0 | — | B |
| Southern Minnesota Independent Living Enterprises & Services, Inc MN | Healthcare & Social Assistance | 0 | — | A |
| Southern Minnesota Inspection MN | Construction | 0 | — | A |
| Southern Minnesota Municipal Power Agency MN | Utilities | 0 | — | A |
| Southern Minnesota Woodcraft MN | Manufacturing | 0 | — | F |
| SOUTHERN MONO HEALTH CARE DISTRICT CA | Healthcare & Social Assistance | 0 | — | D |
| Southern Motion MS | Manufacturing | 0 | — | B |
| Southern Motors of Savannah, Inc GA | Retail Trade | 0 | — | F |
| Southern Mulch LLC LA | Manufacturing | 0 | — | A |
| SOUTHERN NAZARENE UNIVERSITY OK | Educational Services | 1 | $36,088 | — |
| Southern Nevada Adult Mental Health Services NV | Healthcare & Social Assistance | 0 | — | F |
| Southern Nevada Welding NV | Construction | 0 | — | F |
| Southern New England Conference of Seventh-day Adventists MA | Other Services | 1 | $71,143 | — |
| Southern New Hampshire Health NH | Healthcare & Social Assistance | 1 | $69,680 | — |
| Southern New Hampshire Medical Center NH | Healthcare & Social Assistance | 1 | $69,680 | F |
| Southern New Hampshire University NH | Educational Services | 1 | $90,854 | — |
| Southern New Jersey Perinatal Cooperative NJ | Healthcare & Social Assistance | 1 | $70,000 | — |