| Business | Phone |
| Electrical Workers Health 6363 Edna Rd, San Luis Obispo 93401 | (805) 543-8269 |
| Ibew 6363 Edna Rd, San Luis Obispo 93401 | (805) 543-5693 |
| National Assn-Letter Carriers 1026 Chorro St, San Luis Obispo 93401 | (805) 543-7329 |
| Plumbers & Steamfitters Union 3710 Broad St, San Luis Obispo 93401 | (805) 543-2416 |
| San Luis Obispo Cnty Employees 865 Santa Rosa St, San Luis Obispo 93401 | (805) 543-2021 |
| Service Employees Union 974 Santa Rosa St, San Luis Obispo 93401 | (805) 541-2313 |