| South Shore Rehabilitation and Nursing Center NY | Healthcare & Social Assistance | 0 | — | F |
| South Shore Skin Surgeons MA | Healthcare & Social Assistance | 0 | — | A |
| South Shore Transportation OH | Transportation & Warehousing | 0 | — | D |
| South Shore USA, Inc. TX | Transportation & Warehousing | 0 | — | A |
| South Side Control Supply Co IL | Wholesale Trade | 0 | — | A |
| SOUTH SIDE ELECTRIC, INC. ID | Utilities | 0 | — | A |
| South Side Landfill Inc. IN | Administrative & Waste Services | 0 | — | D |
| South Side Moving, LLC MI | Transportation & Warehousing | 0 | — | F |
| South Slope Cooperative Telephone Company ID | Information & Media | 0 | — | F |
| South Snohomish County Fire & Rescue WA | Public Administration | 0 | — | F |
| South Snohomish County Fire and Rescue WA | Public Administration | 0 | — | F |
| South Sound Behavioral Hospital WA | Healthcare & Social Assistance | 0 | — | A |
| SOUTH SOUND COLLEGE HUNKS WA | Transportation & Warehousing | 0 | — | F |
| South Sound Express Delivery, LLC WA | Transportation & Warehousing | 0 | — | F |
| South Sound Final Mile LLC WA | Transportation & Warehousing | 0 | — | F |
| South Sound Inpatient Physicians, PLLC TN | Healthcare & Social Assistance | 1 | $277,326 | — |
| South Sound Inpatient Physicians, PLLC WA | Healthcare & Social Assistance | 18 | $281,662 | — |
| South State Contractors, Inc. KY | Construction | 0 | — | A |
| South Street Seaport Museum NY | Arts & Entertainment | 0 | — | F |
| South Suburban College IL | Educational Services | 0 | — | B |
| South Suburban Sanitary District OR | Utilities | 0 | — | A |
| South Tama County Community School District IA | Educational Services | 3 | $58,900 | — |
| South Tec Development Corporation IL | Real Estate | 0 | — | F |
| SOUTH TEXAS AMBULANCE RESPONSE TX | Healthcare & Social Assistance | 0 | — | A |
| South Texas College of Law Houston, Inc. TX | Educational Services | 2 | $96,192 | — |
| South Texas Community Living Corp TX | Healthcare & Social Assistance | 0 | — | A |
| South Texas Curbing LLC TX | Administrative & Waste Services | 0 | — | A |
| South Texas Educational Technologies, Inc. TX | Educational Services | 1 | $50,190 | — |
| South Texas Electric Coop TX | Utilities | 0 | — | D |
| South Texas Electric Cooperative TX | Utilities | 0 | — | A |
| South Texas Emergency Care Foundation, Inc. TX | Healthcare & Social Assistance | 0 | — | F |
| South Texas Emergency Care Foundation, Inc. - Admin TX | Healthcare & Social Assistance | 0 | — | F |
| South Texas Eye Institute TX | — | 0 | — | — |
| South Texas Gateway Terminal LLC TX | Transportation & Warehousing | 0 | — | A |
| South Texas Health System TX | — | 0 | — | — |
| SOUTH TEXAS JANITORIAL SERVICES, LLC TX | Administrative & Waste Services | 0 | — | A |
| South Texas Lighthouse for the Blind CA | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind HI | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind MI | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind MO | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind MS | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind MT | Manufacturing | 0 | — | A |
| South Texas Lighthouse for the Blind TX | Manufacturing | 0 | — | F |
| South Texas Moulding, Inc. TX | Retail Trade | 0 | — | C |
| South Texas Oil Field Maintenance, Inc. TX | Construction | 0 | — | A |
| South Texas Project Nuclear Operating Company TX | Utilities | 0 | — | A |
| South Texas Rehabilitation Hospital, LP TX | Healthcare & Social Assistance | 0 | — | F |
| South Texas Spine & Surgical Hospital TX | Healthcare & Social Assistance | 0 | — | D |
| South Texas Surgical Hospital TX | Healthcare & Social Assistance | 0 | — | A |
| SOUTH TEXAS UMS LLC TX | Other Services | 0 | — | F |
