| St. Lucie West Services District, FL (CDD) |
| St. Marks, FL (City) |
| St. Martin Parish, LA (County) |
| St. Mary City, KY (City) |
| St. Mary Parish, LA (County) |
| St. Marys, PA (City) |
| St. Marys, IN (Township) |
| St. Marys Township, OH (Township) |
| St. Pete Beach, FL (City) |
| St. Petersburg, FL (City) |
| St. Petersburg, PA (Borough) |
| St. Rose Village, IL (Borough) |
| St. Tammany Parish, LA (County) |
| St. Thomas Township, PA (Township) |
| Stacy, MN (City) |
