| Business | Phone |
| Calhoun County Commissioner 6 Milstead Rd, Port Lavaca 77979 | (361) 552-9656 |
| Calhoun County Commissioner County Rd 101, Port Lavaca 77979 | (361) 552-9242 |
| Calhoun County Courthouse 1300 N Virginia St, Port Lavaca 77979 | (361) 553-8698 |
| Calhoun County E 911 216 E Mahan St, Port Lavaca 77979 | (361) 552-8181 |
| Calhoun County Elections Adm 211 S Ann St, Port Lavaca 77979 | (361) 553-4440 |
| Calhoun County Extension County Rd 101, Port Lavaca 77979 | (361) 552-9747 |
| Calhoun County Extension Highway 238, Port Lavaca 77979 | (361) 552-9747 |
| Calhoun County Flood Plain Adm 211 S Ann St 304, Port Lavaca 77979 | (361) 553-4455 |
| Calhoun County Justice-Peace 201 W Austin St, Port Lavaca 77979 | (361) 553-4621 |
| Calhoun County Juvenile Prbtn 201 W Austin St 9, Port Lavaca 77979 | (361) 553-4670 |
| Calhoun County Landfill Rosenbaum Rd, Port Lavaca 77979 | (361) 552-7133 |
| Calhoun County Maintenance 211 S Ann St, Port Lavaca 77979 | (361) 553-4499 |
| Calhoun County Museum 301 S Ann St, Port Lavaca 77979 | (361) 553-4689 |
| Calhoun County Precinct 3 24627 State Hwy 172, Port Lavaca 77979 | (361) 893-5346 |
| Calhoun County Veteran's Svc 201 W Austin St, Port Lavaca 77979 | (361) 553-4685 |
| Calhoun County Victim Assist 211 S Ann St, Port Lavaca 77979 | (361) 553-4430 |