Oil & Gas Companies in Zavala County, TX
| Company Name | Company Location | Company Type | Most Recent Production |
| 1 | E-Cor, Inc. | Austin, TX 78734 | Gas Operator | Feb 1999 |
| 2 | Eagle Oil & Gas Co. | Dallas, TX 75225 | Oil & Gas Operator | Oct 2025 |
| 3 | Edisto Resources Corp | Houston, TX 77057 | Oil & Gas Operator | Oct 1999 |
| 4 | Egan Resources Inc. | Katy, TX 77494 | Oil & Gas Operator | Oct 2016 |
| 5 | El Toro Resources LLC | Oklahoma City, OK 73134 | Oil & Gas Operator | Oct 2025 |
| 6 | Ellsworth, H. P. O&G Properties | Corpus Chrsti, TX 78413 | Oil & Gas Operator | Oct 2025 |
| 7 | Enre Corp. | San Antonio, TX 78209 | Oil & Gas Operator | Mar 2005 |
| 8 | Esenjay Petroleum Corp. | Corpus Chrsti, TX 78471 | Oil & Gas Operator | Jul 1998 |
| 9 | Espada Operating LLC | San Antonio, TX 78209 | Oil Operator | Oct 2025 |
| 10 | Etoco, L.P. | Houston, TX 77002 | Oil & Gas Operator | Oct 2025 |
| 11 | European-Southwest Co. | Houston, TX 77254 | Oil & Gas Operator | Oct 2025 |
| 12 | Exco Operating Company, LP | Dallas, TX 75251 | Oil & Gas Operator | Oct 2025 |
| 13 | Exotic Oil & Gas LLC | Indiana, PA 15701-3634 | Oil & Gas Operator | Dec 2024 |
| 14 | Exploration Company, The | San Antonio, TX 78258 | Oil & Gas Operator | Jun 2010 |
| 15 | Exxon Corporation | Houston, TX 77210 | Oil & Gas Operator | Jun 2024 |
Production numbers shown above are only for Zavala County, TX and for the production period listed.