Oil & Gas Companies in Petroleum County, MT
| Company Name | Company Location | Company Type | Most Recent Production |
| 1 | Berenergy Corporation | Denver, CO 80217 | Oil & Gas Operator | Aug 2025 |
| 2 | Capitan Operating LLC | Reno, NV 89502 | Oil & Gas Operator | Jan 2013 |
| 3 | Carbon Energy Corporation (USA) | Denver, CO 80290 | Oil & Gas Operator | Jul 2004 |
| 4 | Carrell Oil Company Dba Coco | Laurel, MT 59044 | Oil Operator | Jul 2020 |
| 5 | Cat Creek Holdings LLC | Winnett, MT 59087 | Oil Operator | Jul 2025 |
| 6 | Central Montana Resources, LLC | San Antonio, TX 78209 | Oil Operator | Jul 2015 |
| 7 | Columbia Petroleum, LTD. | Farmington, UT 84025 | Oil Operator | Jul 2025 |
| 8 | R & A Oil, Inc. | Billings, MT 59105 | Oil & Gas Operator | May 2025 |
| 9 | Ranch Oil Company | West Linn, OR 97068 | Oil & Gas Operator | Aug 2025 |
Production numbers shown above are only for Petroleum County, MT and for the production period listed.