| Business | Phone |
| Aquarena Phillips 66 1439 N Ih 35, San Marcos 78666 | (512) 396-0093 |
| Diamond Shamrock 1002 Highway 80, San Marcos 78666 | (512) 396-3448 |
| Diamond Shamrock 510 S Guadalupe St, San Marcos 78666 | (512) 392-6297 |
| Kwik Car Lube & Tune 1000 Highway 80, San Marcos 78666 | (512) 754-6767 |
| Phillips 66 1203 S I H 35, San Marcos 78666 | (512) 396-3566 |
| Quix Gas 1004 N I H 35, San Marcos 78666 | (512) 754-6030 |
| Sac-N-Pac 9315 Ranch Road 12, San Marcos 78666 | (512) 847-1010 |
| San Marcos Shell Station 2201 S I H 35, San Marcos 78666 | (512) 805-8338 |
| Shell 1303 S I H 35, San Marcos 78666 | (512) 396-4554 |
| Texaco Service Station 1903 S I H 35, San Marcos 78666 | (512) 754-6611 |
| Shell Food Mart 934 N Ih 35, San Marcos 78666 | (512) 353-4777 |
| University Exxon 339 N Guadalupe St, San Marcos 78666 | (512) 392-2997 |