| Business | Phone |
| Afscme 320 W G St # 201c, Ontario 91762 | (909) 460-6200 |
| Aldworth Co 5300 Shea Center Dr, Ontario 91761 | (909) 937-0966 |
| Associate Chaffey Teachers 415 N Vineyard Ave # 103, Ontario 91764 | (909) 390-5534 |
| Dairy Employees Union 14397 Euclid Ave, Ontario 91762 | (909) 597-4736 |
| International Association-Mach 1512 E Holt Blvd, Ontario 91761 | (909) 986-6618 |
| Iuecwa Local 1111 1051 S Rockefeller Ave, Ontario 91761 | (909) 390-6313 |
| Office & Professional Employee 4345 E Lowell St # M, Ontario 91761 | (909) 390-6442 |
| United Electrical Radio & Mach 1408 S Grove Ave, Ontario 91761 | (909) 947-8077 |