Missouri - Significance region: Local
| National Bank of Commerce Building |
| National Bank of Rolla Building |
| National Candy Company Factory |
| National Cash Register Company Sales and Repair Building |
| National Cloak and Suit Company |
| Neely Elementary School |
| Neff Tavern Smokehouse |
| Negro Masonic Hall |
| Neighborhood Gardens Apartments |
| Nelson-Pettis Farmsteads Historic District |
| Neosho Commercial Historic District |
| Neosho High School |
| Neosho Wholesale Grocery Company |
| Netter-Ullman Building |
| Nettleton, George H., Home |
| Newbern Hotel |
| Newbill-McElhiney House |
| Newcomer's, D. W., Sons Funeral Home |
| New England Apartments |
| New Franklin Commercial Historic District |
| New Haven Commercial Historic District |
| New Haven Residential Historic District |
| New Hope Primitive Baptist Church |
| New Lebanon Historic District |
| Newman Brothers Building |
| New Mount Sinai Cemetery |
| New York Life Building |
| Nicholson, George E., House |
| Nims Mansion |
| Nipher, Prof. Frances e., House |
| Nooter Corporation Building |
| Norman School |
| Norris, Jewett, Library |
| North Broadway Glass and Plow Warehouse District |
| North Broadway Wholesale and Warehouse District |
| Northeast Douglas Street Residential Historic District |
| Northeast Forest Avenue and Northeast Green Street Residential Historic District |
| Northeast Green and 1st Streets Residential Historic District |
| Northern Methodist Episcopal Church of Clarksville |
| North, James, House |
| North Main Street Historic District |
| North Ninth Street Historic District |
| North Riverfront Industrial Historic District |
| North Taylor Avenue Historic District |
| North Third Street Historic District |
| North Ward School |
| Norwood Hills Country Club |
| Oakherst Place Concrete Block District |
| Oak Hill Historic District |
| Oakley Chapel African Methodist Episcopal Church |
| Oakview Place Apartments |
| Oakwood Country Club |
| O'Bannon Homestead |
| Oberman, D.M., Manufacturing Co. Building |
| Odessa Ice Cream Company Building |
| Oehler Brick Buildings |
| O'Hara, Mark, House |
| Old Appleton Bridge |
| Old Barnhill Building |
| Old Calabosse |
| Old California City Hall and Fire Station |
| Old City Hall |
| Old Eminence Site (23SH104) |
| Old Ferguson West Historic District |
| Old Gerald School |
| Old Greenville (23WE637) |
| Old Lorimier Cemetery |
| Old McDonald County Courthouse |
| Old McDonald County Jail |
| Old Rock House |
| Old St. Patrick's Church |
| Old Town Historic District |
| Old Webster Historic District |
| Old Webster Historic District |
| Olean Railroad Depot |
| Olive and Locust Historic Business District |
| Olive Chapel African Methodist Episcopal Church |
| Olivia Apartments |
| Olympia, The |
| One Bell Center |
| Onyx Cave |
| Opera Hall Block |
| Orchard Acres |
| Orrville Historic District |
| Osage County Poorhouse |
| Osage Farms Type 315:13 Government Farmhouse |
| Osage Farms Unit No. 1 Historic District |
| Osage Farms Unit No. 25 Historic District |
| Osage Farms Unit No. 26 Historic District |
| Osage Farms Unit No. 30 Historic District |
| Osage Farms Unit No. 31 |
| Osage Farms Unit No. 41 |
| Osage Farms Unit No. 43 Historic District |
| Osage Farms Units No. 5 and No. 6 Historic District |
| Osage Farms Units No. 8 and No. 9 Historic District |
| Osage Hills School |
| Osceola Public School Building |
| Ostertag, Robert, House |
| Our Lady of Perpetual Help Parish Hall, School, Convent, and Rectory |
| Owens, Given, House |
Data from United States Park Service and Wikidata
