All - Architectural style - Neoclassical architecture
| Mt. Zion Presbyterian Church |
| Mudbaden Sulphur Springs Company |
| Muirdale Tuberculosis Sanatorium |
| Mulford Building |
| Multnomah County Courthouse |
| Muncie Public Library |
| Munger Place Historic District |
| Municipal Auditorium |
| Municipal Building |
| Municipal Building |
| Municipal Building |
| Municipal Lighting and Waterworks Plant |
| Munro-M.A. Hanna Mining Company Office Building |
| Murillo Flats |
| Murphey School |
| Murphy, Daniel F., House |
| Murphysboro Elks Lodge |
| Murphy, William J., House |
| Murrah House |
| Murray County Courthouse |
| Murray County Courthouse |
| Murray, James F., House |
| Mutual Aid Union Building |
| Myers, John B., House |
| Myrtlewood |
| Nacogdoches Downtown Historic District |
| Nash, William R., House |
| National Academy of Sciences |
| National Archives |
| National Bank of Commerce Building |
| National Biscuit Company Building |
| National Company Building |
| National Home, Daughters of America |
| National Hotel |
| National State Bank |
| National War College |
| Naval Armory-Convention Hall |
| Nave, Royston, Memorial |
| Nazing Court Apartments |
| Neal Terrace |
| Nebot, Zaldo de, Residencia |
| Nebraska Governor's Mansion |
| Neely Elementary School |
| Negaunee State Bank Building |
| Nelson School |
| Nesbitt, J.J., House |
| Nesquehoning High School |
| Newark High School |
| Newark Penn Station and Dock Bridge (Boundary Increase) |
| Newberry College Historic District |
| New England Telephone and Telegraph Engineering Office |
| New England Telephone Building |
| New Hampshire Bank Building |
| New Iberia High School |
| New Orpheum Theatre |
| New Perry Hotel |
| New Plymouth Congregational Church |
| New Straitsville School |
| New York Savings Bank |
| New York School of Applied Design |
| New York Stock Exchange |
| New York Studio School of Drawing, Painting and Sculpture |
| Ney, Elisabet, Studio and Museum |
| Niagara County Courthouse and County Clerk's Office |
| Niagara Falls School District Administration Building |
| Nicholas County Bank |
| Nicholas County Courthouse |
| Nicholls, Francis T., Junior College Main Building |
| Nicholson, George E., House |
| Nicolay House |
| Noble-Kendall House |
| Noerenberg Estate Barn |
| Nonnenmacher House |
| Norfolk And Western Railroad Depot |
| Norfolk Carnegie Library |
| North Broad Street Station, Reading Company |
| Northern Pacific Depot |
| Northern States Life Insurance Company |
| North Little Rock City Hall |
| North Little Rock Post Office |
| North Presbyterian Church |
| North Pumping Station |
| North Side School |
| North Topeka Baptist Church |
| Northumberland Apartments |
| Northwest Davenport Savings Bank |
| Norwalk Memorial Hospital |
| Nuckolls County Courthouse |
| Nuckolls-Jefferies House |
| Nueces County Courthouse |
| Oakes Hotel Building |
| Oak Hill Estate |
| Oak Hill Mausoleum |
| Oakland Free Library-Melrose Branch |
| Oakland Public Library |
| Oaks, The |
| Oakwold Plantation House |
| Oates House |
| Oates, John A., House |
| Oberg-Metcalf House |
Data from United States Park Service and Wikidata
