Idaho - Criteria: C (architecture/engineering)
| Post Falls Community United Presbyterian Church |
| Poulson, Jim, House |
| Pound, Homer, House |
| Power County Courthouse |
| Prairie School II |
| Price, Dan, House |
| Price, Fred, Bungalow |
| Price, Herber, Bungalow |
| Price, Joe, House |
| Price, Robert, House |
| Priestly's Hydraulic Ram |
| Quay, Greer and Jennie, House |
| Quinn Apartments |
| Ramona Theater |
| Ream, William and Nora, House |
| Reclamation Service Boise Project Office |
| Regan, John, American Legion Hall |
| Reiger, Fred, Houses |
| Relic Hall |
| Rexburg Stake Tabernacle |
| Rice, John C., House |
| Rice Meetinghouse |
| Rice-Packard House |
| Rich, William L., House |
| Ricketts, Julian T., House |
| Ridenbaugh Hall |
| Riggins Motel |
| Ririe A Pegram Truss Railroad Bridge |
| Ririe B Pegram Truss Railroad Bridge |
| Roberts, Morris, Store |
| Rocky Mountain Bell Telephone Company Building |
| Rocky Point CCC Properties |
| Rogers, Franklin, Bungalow |
| Rogers, Frederick, House |
| Roosevelt School |
| Roosevelt School |
| Rosedale Odd Fellows Temple |
| Rose Lake School II |
| Ross Fork Episcopal Church |
| Ross Fork Oregon Short Lines Railroad Depot |
| Rossi, Mrs. A. F., House |
| Roswell Grade School |
| Rowles, Donaldson, House |
| Ruatsale, Matt, Homestead |
| Sack, Johnny, Cabin |
| Salmon City Hall and Library |
| Salmon Falls Dam |
| Salmon Mountain Lookout |
| Salmon Odd Fellows Hall |
| Sandpoint Burlington Northern Railway Station |
| Sandpoint Community Hall |
| Sandpoint Federal Building |
| Sandpoint High School |
| Sandpoint Historic District |
| Schick, Henry, Barn |
| Schmelzel, H. A., House |
| Schmerschall, John F., House |
| Schreiber, Adolph, House |
| Scofield, Anna Nielsen, House |
| Scott, Josiah, House |
| Sealander, Carl S. and Lizzie, Farmstead |
| Sensenig, Emerson and Lucretia, House |
| Settlement School |
| Shane Building |
| Shelton L.D.S. Ward Chapel |
| Shepard, L. Fay, House |
| Shepherd Bungalow |
| Shepherd, Earl, Bungalow |
| Shepherd, J. R., House |
| Shepherd, Les and Hazel, Bungalow |
| Shepherd, Ted, Cottage |
| Shilling Avenue Historic District |
| Short, O. F., House |
| Shoshone Historic District |
| Shoup Building |
| Sidenfaden, William, House |
| Sigma Alpha Epsilon Fraternity House |
| Silbaugh, W. H., House |
| Silva, Arthur D., Water Tank |
| Silva, Manuel, Barn |
| Simpson, W. A., House |
| Skattaboe Block |
| Skillern, John, House |
| Smedley, Thomas, House |
| Smith, C. Harvey, House |
| Smith, Nathan, House |
| Snow, Arthur, House |
| Snyder Guard Station Historical District |
| Soda Springs City Hall |
| Soderling, Russell and Pearl, House |
| Sommercamp, Mary Elizabeth, House |
| Sommer, Morris, House |
| Soncarty, Edward and Ida, Barn |
| South Boise Fire Station |
| South Eighth Street Historic District |
| Southern Idaho Timber Protective Association (SITPA) Buildings |
| Spencer Rock House |
| Spirit Lake Historic District |
| Spokane & International Railroad Construction Camp |
| St. Agnes Catholic Church |
Data from United States Park Service and Wikidata
