Montana - Area of significance: Architecture
| Stoltz House |
| Stone Homestead |
| Story Motor Company |
| Stout, John, House |
| St. Paul's Episcopal Church |
| St. Paul’s Mission Church |
| St. Peter's Catholic Church |
| St. Peter's Mission Church and Cemetery |
| St. Philip's Episcopal Church |
| St. Richard's Church |
| Studebaker Building |
| St. Wenceslaus Catholic Church |
| Sullivan, James J., House |
| Sullivan Rooming House |
| Summers-Quast Farmstead |
| Summit Lodge |
| Sun Camp Fireguard Cabin |
| Superintendent's House |
| Superior School |
| Suydam, Hester E., Boarding House |
| Swan Lake Rock House Historic District |
| Swanson Boathouse |
| Swanson Homestead |
| Swiftcurrent Auto Camp Historic District |
| Swiftcurrent Fire Lookout |
| Swiftcurrent Ranger Station Historic District |
| Symes Hotel |
| Taylor, Ray E., House |
| Temple Emanu-El |
| Teton County Courthouse |
| Thayer House |
| Thexton Ranch |
| Thibodeau Electric Shop |
| Thierwechter House |
| Thompson Falls Hydroelectric Dam Historic District |
| Thorn House |
| Thornton Hospital |
| Thornwood School |
| Three Forks of the Missouri |
| Three Valleys State Bank |
| Toole, John R., House |
| Torgrimson Place |
| Trident School |
| Trosdahl, Erick, House |
| Trowbridge Dairy |
| Troy Jail |
| Trytten, J. M., House |
| Tupper, J. S., House |
| Two Medicine Campground Camptender's Cabin |
| Two Medicine General Store |
| Unemployment Compensation Commission Building |
| Union League of America Hall |
| United Methodist Episcopal Church |
| University Apartments |
| University Area Historic District |
| University of Montana Historic District |
| Upper Kintla Lake Patrol Cabin |
| Upper Lake McDonald Ranger Station Historic District |
| Upper Logging Lake Snowshoe Cabin |
| Upper Madison School |
| Upper Nyack Snowshoe Cabin |
| Upper Park Creek Patrol Cabin |
| Urbach Cabin |
| Ursuline Academy |
| Ursuline Convent of the Sacred Heart |
| US Customs Building |
| US Post Office |
| US Post Office-Anaconda Main |
| US Post Office and Courthouse-Billings |
| US Post Office and Courthouse-Glasgow Main |
| US Post Office and Courthouse-Great Falls |
| US Post Office and Courthouse-Havre Main |
| US Post Office and Federal Building-Lewistown |
| US Post Office-Dillon Main |
| US Post Office-Livingston Main |
| US Post Office-Miles City Main |
| Valier Public School |
| Valley Masonic Lodge No. 21 |
| Vananda Historic District |
| Van Camp-Tash Ranch |
| Vance Lodge |
| VFW Club |
| Virgelle Mercantile and Virgelle State Bank |
| Waddell, George, House |
| Walker House |
| Wallin, Frank, House |
| Walsh's, Johnnie, Guest Lodge |
| Walsh, Thomas J., Lodge |
| Walton Ranger Station Historic District |
| Wamsley, Other C., House |
| Wargelin-Warila Homestead |
| Warila Boarding House and Sauna |
| Washoe Theater |
| Wassweiler Hotel and Bath Houses |
| Watkins Creek Ranch |
| Wellman Block |
| West Entrance Station |
| Western Clay Manufacturing Company |
| Western Life Insurance Company Helena Branch Office |
| West Fork Butte Lookout |
Data from United States Park Service and Wikidata
