Oklahoma - Criteria: C (architecture/engineering)
| Guthrie Historic District |
| Hadley House |
| Hadley, Walter, House |
| Hales, W. T., House |
| Harding Junior High School |
| Hargis-Mitchell-Cochran House |
| Harmon County Courthouse |
| Harper County Courthouse |
| Harrison School |
| Harwelden |
| Haskell County Courthouse |
| Hatashita, Henry C., House |
| Hayes-Kennedy-Rivoli Theater Building |
| Healdton Armory |
| Healdton Oil Field Bunk House |
| Hedlund Motor Company Building |
| Heritage Hills Historic and Architectural District |
| Hightower Building |
| Hines Round Barn |
| Hobart Rock Island Depot |
| Holdenville Armory |
| Holy City of the Wichitas Historic District |
| Holy Family Cathedral, Rectory, and School |
| Hominy Armory |
| Hominy Osage Round House |
| Hooker Woodframe Grain Elevator |
| Hopewell Baptist Church |
| Hotel Aldridge |
| Hotel Cherokee |
| Hotel Franklin |
| Hotel Vinita |
| Hughes, George, House |
| Hugo Armory |
| Hugo Public Library |
| Idabel Armory |
| Immaculate Conception Church |
| India Temple Shrine Building |
| Ingersoll Tile Elevator |
| International Temple, Supreme Assembly, Order of the Rainbow for Girls |
| I.O.O.F. Building of Buffalo |
| I.O.O.F. Hall |
| Irving Baptist Church |
| Jackson Conoco Service Station |
| Jackson County Courthouse |
| Jackson School |
| Jacobson, Oscar B., House |
| Jefferson County Courthouse |
| Johnson Home |
| Johnson House |
| Joyce House |
| Kaw City Depot |
| Kay County Courthouse |
| Kenwood Historic District |
| Kimmell Barn |
| Kingfisher Armory |
| Kinta High School |
| Kiowa County Courthouse |
| Kisner, Robert R. and Minnie L., House |
| Knowles Grain Elevator |
| Konawa Armory |
| Lake Murray State Park |
| Lake Overholser Bridge |
| Lake Ponca Duck Pond Historic District |
| Lamerton House |
| La Quinta |
| Laverne's North Main Street District |
| Lawton High School |
| Lawton National Guard Armory |
| Ledbetter, H.E., House |
| Lee, Robert E., School |
| Little Cabin Creek Bridge |
| Little Deep Fork Creek Bridge |
| Logan Apartments |
| Logan County Courthouse |
| Long Branch Creek Bridge |
| Love County Courthouse |
| Love County Jail and Sheriff's Residence |
| Mahoney House and Garage |
| Major County Courthouse |
| Mangum Armory |
| Mangum Community Building |
| Manhattan Building |
| Maple Ridge Historic Residential District |
| Marland Filling Station |
| Marland-Paris House |
| Marshall County Courthouse |
| Marshall Hall |
| Mascho Building and Public Privy |
| Masonic Temple |
| Mayo Hotel |
| McAlester House |
| McAlester Scottish Rite Temple |
| McAllister House |
| McBirney, James H., House |
| McClain County Courthouse |
| McClung House |
| McCristy-Knox Mansion |
| McGraw, James J., House |
| McLain Rogers Park |
| McNaughton, John Patrick, Barn |
Data from United States Park Service and Wikidata
