Oil & Gas Companies in Ellis County, KS
| Company Name | Company Location | Company Type | Most Recent Production |
| 1 | R. J. Oil Co. | Olney, TX 76374 | Oil & Gas Operator | May 2025 |
| 2 | R. P. Nixon Operations, Inc | Hays, KS 67601 | Oil Operator | Jun 2025 |
| 3 | Rains & Williams | | Oil & Gas Operator | Nov 1995 |
| 4 | Rains And Williamson Oil Co. | Wichita, KS 67277 | Oil & Gas Operator | Jun 2025 |
| 5 | Rama Operating Co., Inc. | Stafford, KS 67578 | Oil & Gas Operator | Jun 2025 |
| 6 | Raney Oil Company, LLC | Lawrence, KS 66049 | Oil & Gas Operator | Jun 2025 |
| 7 | Range Oil Co., Inc. | Wichita, KS 67278 | Oil & Gas Operator | Jan 2020 |
| 8 | Range Oil Compan | | Oil & Gas Operator | Nov 1995 |
| 9 | Rapid Well Service, Inc. | Russell, KS 67665 | Oil Operator | Jun 2025 |
| 10 | Raymond Oil Co., Inc. | Wichita, KS 67201 | Oil & Gas Operator | Jun 2025 |
| 11 | Raymond Oil Comp | | Oil & Gas Operator | Dec 1996 |
| 12 | Reach Petroleum | | Oil & Gas Operator | Jan 1994 |
| 13 | Rebel Oil LLC | | Oil Operator | Jun 2025 |
| 14 | Reddig Enterprises Inc. | Gorham, KS 67640 | Oil Operator | Jun 2025 |
| 15 | Reef Operating, Inc. | Hays, KS 67601 | Oil Operator | Jun 2025 |
| 16 | Reif Oil Operati | | Oil Operator | Nov 1988 |
| 17 | Resource Operations, Inc. | Tulsa, OK 74157 | Oil & Gas Operator | May 2016 |
| 18 | Richland Oil Investments, LLC | Palco, KS 67657 | Oil Operator | Jun 2025 |
| 19 | Ritchie Explorat | | Oil & Gas Operator | Dec 1996 |
| 20 | Ritchie Exploration | | Oil Operator | Aug 1995 |
| 21 | Ritchie Exploration, Inc. | Wichita, KS 67278 | Oil & Gas Operator | Jun 2025 |
| 22 | Roberts Brothers | | Oil Operator | Oct 1993 |
| 23 | Robinowitz Oil C | | Oil Operator | Dec 1996 |
| 24 | Rock Creek Resources LLC | Englewood, CO 80112 | Oil & Gas Operator | Dec 2021 |
| 25 | Royal Drilling Inc | Russell, KS 67665 | Oil Operator | Jun 2025 |
| 26 | Russell Oil, Inc. | Edmond, OK 73083 | Oil Operator | Jun 2025 |
Production numbers shown above are only for Ellis County, KS and for the production period listed.