| San Juan County, NM (County) |
| San Juan County, UT (County) |
| San Leandro, CA (City) |
| San Leanna, TX (Village) |
| San Luis, AZ (City) |
| San Luis, CO (Town) |
| San Luis Obispo, CA (City) |
| San Luis Obispo County, CA (County) |
| San Marcos, CA (City) |
| San Marcos, TX (City) |
| San Marino, CA (City) |
| San Mateo, CA (City) |
| San Mateo County, CA (County) |
| San Miguel County, CO (County) |
| San Miguel County, NM (County) |
