| 1901 | Helmerich & Payne, Inc. | Tulsa, OK 74114 | Oil & Gas Operator | Aug 2025 |
| 1902 | Helsel, Allan J | South Haven, KS 67140 | Oil Operator | Apr 2025 |
| 1903 | Hembree Oil Production, LLC | Great Bend, KS 67530 | Oil Operator | Jun 2025 |
| 1904 | Hembree Robert F | | Oil Operator | Dec 2009 |
| 1905 | Henderson, Chris | Pawhuska, OK 74056 | Oil Operator | Dec 2009 |
| 1906 | Hennessy Oil Com | | Oil Operator | Mar 1991 |
| 1907 | Hensley Oil Company LLC | Arkansas City, KS 67005 | Oil Operator | Jun 2025 |
| 1908 | Hensley, Cloide J. & Hazel M. | Arkansas City, KS 67005 | Oil Operator | Sep 2001 |
| 1909 | Heritage Oil L.L.C. | Hays, KS 67601 | Oil Operator | Jun 2025 |
| 1910 | Herman Krug - Oil Operations | | Oil Operator | Jun 2025 |
| 1911 | Herman L. Loeb LLC | Lawrenceville, IL 62439 | Oil & Gas Operator | Jun 2025 |
| 1912 | Herman Lang Oil And Gas Co. | | Oil & Gas Operator | Dec 1992 |
| 1913 | Hermreck Oil Com | | Oil & Gas Operator | Aug 1996 |
| 1914 | Hermreck Oil Company | | Oil Operator | Nov 2024 |
| 1915 | Hertel Oil Company | | Oil Operator | Nov 2018 |
| 1916 | Hertel Oil Company LLC | Hays, KS 67601 | Oil Operator | Jun 2025 |
| 1917 | Hess Oil Company | McPherson, KS 67460 | Oil & Gas Operator | Jun 2025 |
| 1918 | Hesse Petroleum Co.,L.L.C. | Wichita, KS 67208 | Oil & Gas Operator | Jun 2025 |
| 1919 | Hessert Edward C | | Oil & Gas Operator | Sep 1993 |
| 1920 | Hessert Loc Inc | Carl Junction, MO 64834 | Oil Operator | Dec 2009 |
| 1921 | Hett Oil & Gas, LLC | Lincolnville, KS 66858 | Oil & Gas Operator | Jun 2025 |
| 1922 | Hewitt Energy Group Inc | Salt Lake City, UT 84111 | Oil & Gas Operator | Apr 2015 |
| 1923 | HG Oil Holdings, LLC | Hoisington, KS 67544 | Oil & Gas Operator | Jun 2025 |
| 1924 | Hi-Kat Petroleum | | Oil Operator | Mar 1990 |
| 1925 | Hi-Kat Petroleum Company | Liberal, KS 67905-1261 | Oil & Gas Operator | May 2014 |
| 1926 | Hibernian Compan | | Oil & Gas Operator | Feb 1991 |
| 1927 | Hicks Exploration, LLC | Dover, OK 73734 | Gas Operator | Feb 2025 |
| 1928 | Hiebert & Wedel | | Oil & Gas Operator | May 1995 |
| 1929 | Hiebert, D. O. Lewis | McPherson, KS 67460 | Oil Operator | Feb 1999 |
| 1930 | Higginbottom Engineering, Inc. | Liberal, KS 67905 | Oil & Gas Operator | Jun 2025 |
| 1931 | Higgins Oil & Ga | | Oil Operator | Apr 1992 |
| 1932 | High Bluff Operating, LLC | Littleton, CO 80161 | Oil & Gas Operator | May 2018 |
| 1933 | High Plains Oil | | Oil Operator | Jun 1989 |
| 1934 | High Plains Production, LLC | Murray, KY 42071 | Oil & Gas Operator | Dec 2024 |
| 1935 | High Point Produ | | Gas Operator | May 1996 |
| 1936 | Hill Oil And Gas Co., Inc. | Overland Park, KS 66213 | Oil Operator | Mar 2020 |
| 1937 | Hillary Oil Comp | | Oil & Gas Operator | Apr 1991 |
| 1938 | Hillenburg Oil C | | Oil Operator | Apr 1994 |
| 1939 | Hillenburg Oil Co., A General Partnership | Broken Arrow, OK 74011 | Oil Operator | Jun 2025 |
| 1940 | Hilliker Oil Com | | Oil Operator | Jul 1984 |
| 1941 | Hilliker Production | Indian Wells, CA 92210 | Oil & Gas Operator | Jul 2007 |
| 1942 | Hilltop Exploration, Inc. | Sedan, KS 67361 | Oil Operator | Jan 2000 |
| 1943 | Himco Oil & Gas Inc | Enid, OK 73702 | Oil & Gas Operator | Aug 2025 |
| 1944 | Hinkle Oil Compa | | Oil & Gas Operator | Nov 1994 |
| 1945 | Hinkle Oil Company | Wichita, KS 67202 | Oil & Gas Operator | Jan 1999 |
| 1946 | Hinks Petroleum Co., Inc. | Wichita, KS 67201 | Oil Operator | May 1999 |
| 1947 | Hirt Farms Incor | | Oil & Gas Operator | Apr 1994 |
| 1948 | Hizey Service & | | Oil Operator | Apr 1994 |
| 1949 | HJ, Inc. | Garden City, KS 67846 | Oil & Gas Operator | Jun 2025 |
| 1950 | HKW Oil Company, Inc. | Bunker Hill, KS 67626 | Oil Operator | Dec 2009 |
| 1951 | HMN Partnership | Argonia, KS 67004 | Oil Operator | Nov 1993 |
| 1952 | Hodges & Hodges Oil Venture | Gallup, NM 87301 | Oil Operator | May 1999 |
| 1953 | Hodges Oil | | Oil Operator | Jun 2025 |
| 1954 | Hodges, Dennis D. And Peggy D. | Reading, KS 66868 | Oil Operator | Jun 2025 |
| 1955 | Hoehn Oil | Wellsville, KS 66092 | Oil Operator | Oct 1998 |
| 1956 | Hoehn Oil LLC | Wellsville, KS 66092 | Oil Operator | Jun 2025 |
| 1957 | Hoener Ross Inco | | Oil Operator | Dec 1991 |
| 1958 | Hoener, Ross | Iuka, KS 67066 | Oil & Gas Operator | May 2025 |
| 1959 | Hoepker, Larry | Humboldt, KS 66748 | Oil Operator | Dec 2024 |
| 1960 | Hoff Oil & Gas | | Oil Operator | May 2013 |
| 1961 | Hoffman Oil, Inc. | Claflin, KS 67525 | Oil Operator | Jun 2025 |
| 1962 | Hoffman Petroleu | | Oil Operator | Sep 1989 |
| 1963 | Hoffman Petroleum, Inc. | Littleton, CO 80120 | Oil Operator | Sep 1996 |
| 1964 | Hoffman Resources LLC | Hoisington, KS 67544 | Oil & Gas Operator | Jun 2025 |
| 1965 | Hoffman, Brian | Claflin, KS 67525 | Oil Operator | May 2025 |
| 1966 | Hoffman, Myrle F. | Denver, CO 80202 | Oil Operator | Dec 1986 |
| 1967 | Hogoboom Al Oilf | | Oil Operator | Oct 1990 |
| 1968 | Holcomb Oil Comp | | Oil Operator | Sep 1991 |
| 1969 | Holland Assoc | | Oil Operator | Sep 1987 |
| 1970 | Holt IVan | | Oil Operator | Mar 1989 |
| 1971 | Holt IVan Leroy | | Oil & Gas Operator | Jan 1994 |
| 1972 | Holt Oil & Gas C | | Oil Operator | Sep 1984 |
| 1973 | Holt, Carol | Independence, KS 67301 | Oil Operator | Feb 2025 |
| 1974 | Holt, Roger | Cherryvale, KS 67335 | Gas Operator | Mar 2003 |
| 1975 | Holtom, Bill, A General Partnership | Saint Paul, KS 66771 | Oil Operator | Jun 2024 |
| 1976 | Holton Brothers | Canton, KS 67428 | Oil Operator | Apr 1990 |
| 1977 | Home-Stake Royalty Corp., The | Tulsa, OK 74103 | Oil & Gas Operator | Feb 2014 |
| 1978 | Hon R J Oil & Ga | | Oil Operator | Nov 1990 |
| 1979 | Hondo Oil & Gas | Houston, TX 77042 | Oil & Gas Operator | Oct 1995 |
| 1980 | Honey Oil Co | Wichita, KS 67226 | Oil & Gas Operator | Mar 2009 |
| 1981 | Honey Well, LLC | Lenexa, KS 66219 | Oil Operator | May 2025 |
| 1982 | Hoover Noble C | | Oil Operator | Nov 1992 |
| 1983 | Hope Company, LLC | Longmont, CO 80502 | Gas Operator | Feb 2012 |
| 1984 | Hopewell Operating, Inc. | Shreveport, LA 71101 | Oil & Gas Operator | Dec 2025 |
| 1985 | Hoppe Oil & Gas | | Oil Operator | Nov 1992 |
| 1986 | Hoppe Oil & Gas Co., Inc. | Wichita, KS 67202 | Oil Operator | Jul 1998 |
| 1987 | Hopper Oil Co., Inc. | Winfield, KS 67156 | Oil Operator | Jun 2025 |
| 1988 | Hopper Oil Compa | | Oil Operator | Sep 1988 |
| 1989 | Horizon Oil & Ga | | Oil & Gas Operator | Jan 1992 |
| 1990 | Horizontal Development & Production Inc | Lubbock, TX 79493 | Oil & Gas Operator | Jul 2002 |
| 1991 | Horner Richard R | | Gas Operator | May 1995 |
| 1992 | Horseshoe Operating Inc. | Midland, TX 79701 | Oil & Gas Operator | Jan 2023 |
| 1993 | Horst Oil, LLC | Pittsburg, MO 65724 | Oil Operator | Dec 2009 |
| 1994 | Horton Oil Company | Independence, KS 67301 | Oil & Gas Operator | Jul 2000 |
| 1995 | Horton, Jack | Independence, KS 67301 | Oil & Gas Operator | Aug 2015 |
| 1996 | Horton, John | Sedan, KS 67361 | Oil & Gas Operator | Jun 2025 |
| 1997 | House, Dustin | Shawnee, KS 66218 | Oil Operator | May 2025 |
| 1998 | Housel John R Jr | | Oil Operator | Oct 1994 |
| 1999 | Housel, Robert E. | Cherryvale, KS 67335 | Oil & Gas Operator | Dec 2003 |
| 2000 | Houston Hydrolan | | Oil Operator | Jul 1984 |