Oil & Gas Companies in Seward County, KS
| Company Name | Company Location | Company Type | Most Recent Production |
| 1 | H & C Oil Operat | | Oil & Gas Operator | Dec 1996 |
| 2 | H & C Oil Operating Inc. | Plainville, KS 67663 | Oil & Gas Operator | Jun 2025 |
| 3 | H & L Operating Company | Amarillo, TX 79114 | Oil & Gas Operator | Feb 2020 |
| 4 | H. I., Inc. | Liberal, KS 67901 | Oil & Gas Operator | Feb 2012 |
| 5 | Harris Oil & Gas | | Oil & Gas Operator | Jul 1995 |
| 6 | Harris Oil & Gas Company | Denver, CO 80202 | Oil & Gas Operator | Jun 2016 |
| 7 | Hasada Industrie | | Oil & Gas Operator | Jul 1995 |
| 8 | Helmerich & Payn | | Oil & Gas Operator | Aug 1995 |
| 9 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Sep 2025 |
| 10 | Herman L. Loeb LLC | Lawrenceville, IL 62439 | Oil & Gas Operator | Jun 2025 |
| 11 | Herman Lang Oil And Gas Co. | | Oil & Gas Operator | Dec 1992 |
| 12 | HG Oil Holdings, LLC | Hoisington, KS 67544 | Oil & Gas Operator | Jun 2025 |
| 13 | Hicks Exploration, LLC | Dover, OK 73734 | Gas Operator | Feb 2025 |
| 14 | Higginbottom Engineering, Inc. | Liberal, KS 67905 | Oil & Gas Operator | Jun 2025 |
| 15 | High Point Produ | | Gas Operator | May 1996 |
| 16 | HJ, Inc. | Garden City, KS 67846 | Oil & Gas Operator | Jun 2025 |
| 17 | Horizon Oil & Ga | | Oil & Gas Operator | Jan 1992 |
| 18 | Huber J M Corp | Edison, NJ 08837 | Oil & Gas Operator | Dec 2025 |
| 19 | Huber J M Corpor | | Oil & Gas Operator | Dec 1996 |
| 20 | Hudson Brothers, Inc. | Hutchinson, KS 67501 | Oil & Gas Operator | Jun 2007 |
| 21 | Hugoton Energy C | | Oil & Gas Operator | Feb 2004 |
| 22 | Hugoton Energy Corporation | Oklahoma City, OK 73113 | Oil & Gas Operator | Dec 2019 |
| 23 | Hummon Corp | Medicine Lodge, KS 67104 | Oil & Gas Operator | Apr 2023 |
Production numbers shown above are only for Seward County, KS and for the production period listed.