Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Garland Post Office (historical) | Post Office | 788 | Custer | 46 02 54 N | 105 55 50 W |
| Garland School (historical) | School | 794 | Custer | 46 01 45 N | 105 57 41 W |
| Garlick Heliport | Airport | 1105 | Ravalli | 46 12 24 N | 114 09 14 W |
| Garlick Lake | Lake | 908 | Flathead | 48 10 36 N | 114 05 15 W |
| Garlipee Ranch | Locale | 1301 | Lewis and Clark | 47 22 27 N | 112 05 04 W |
| Garneau School (historical) | School | 805 | Sheridan | 48 41 16 N | 104 53 47 W |
| Garneill | Populated Place | 1348 | Fergus | 46 45 09 N | 109 45 10 W |
| Garneill (historical) | Locale | 1348 | Fergus | 46 45 09 N | 109 45 10 W |
| Garneill Cemetery | Cemetery | 1350 | Fergus | 46 45 05 N | 109 45 05 W |
| Garneill Elevator | Locale | 1350 | Fergus | 46 45 05 N | 109 45 05 W |
| Garneill Post Office (historical) | Post Office | 1348 | Fergus | 46 45 09 N | 109 45 10 W |
| Garners Gulch | Valley | | Teton | 47 53 07 N | 112 46 55 W |
| Garnet | Populated Place | 1800 | Granite | 46 49 31 N | 113 20 20 W |
| Garnet Creek | Stream | | Flathead | 47 38 37 N | 113 26 21 W |
| Garnet Gold Mine | Mine | 1966 | Madison | 45 38 43 N | 111 56 12 W |
| Garnet Gold Mine | Mine | 2122 | Madison | 45 38 60 N | 111 56 03 W |
| Garnet Lake | Lake | 1252 | Flathead | 48 57 24 N | 114 27 06 W |
| Garnet Mine | Mine | 1850 | Granite | 46 49 28 N | 113 20 45 W |
| Garnet Mountain | Summit | 2500 | Gallatin | 45 25 36 N | 111 12 23 W |
| Garnet Peak | Summit | 2481 | Flathead | 47 36 48 N | 113 26 52 W |
| Garnet Post Office (historical) | Post Office | 1800 | Granite | 46 49 31 N | 113 20 20 W |
| Garnet Range | Range | 1833 | Powell | 46 43 18 N | 112 57 33 W |
| Garnet School (historical) | School | 1800 | Granite | 46 49 31 N | 113 20 20 W |
| Garnier Creek | Stream | | Flathead | 48 22 28 N | 114 13 25 W |
| Garr Canyon | Valley | | Beaverhead | 44 40 35 N | 112 41 31 W |
| Garr Reservoir | Reservoir | 952 | Powder River | 45 20 13 N | 105 29 58 W |
| Garr Spring | Spring | 2189 | Beaverhead | 44 38 57 N | 112 43 13 W |
| Garr Spring Number Three | Spring | 2201 | Beaverhead | 44 38 55 N | 112 43 13 W |
| Garr Spring Number Two | Spring | 2250 | Beaverhead | 44 38 55 N | 112 43 35 W |
| Garrard Lake | Lake | 2193 | Ravalli | 46 19 34 N | 114 21 15 W |
| Garrett Hill | Summit | 2416 | Beaverhead | 45 19 11 N | 113 03 35 W |
| Garrett Hill Mine | Mine | 2334 | Beaverhead | 45 18 60 N | 113 03 03 W |
| Garrett Mobile Home Park | Populated Place | 1013 | Cascade | 47 30 20 N | 111 21 03 W |
| Garrigus Ditch | Canal | 1232 | Stillwater | 45 32 34 N | 109 26 10 W |
| Garrison | Locale | 1333 | Powell | 46 31 24 N | 112 48 42 W |
| Garrison | Populated Place | 1333 | Powell | 46 31 24 N | 112 48 42 W |
| Garrison (historical) | Populated Place | 1021 | Cascade | 47 22 50 N | 111 33 33 W |
| Garrison Cabin | Locale | 1965 | Madison | 45 02 21 N | 112 01 46 W |
| Garrison Elementary School | School | 1332 | Powell | 46 31 30 N | 112 48 26 W |
| Garrison Mine | Mine | 2397 | Madison | 45 12 04 N | 111 57 04 W |
| Garrison Mine | Mine | 2403 | Madison | 45 11 60 N | 111 57 03 W |
| Garrison Post Office (historical) | Post Office | 1333 | Powell | 46 31 24 N | 112 48 42 W |
| Garrison School (historical) | School | 716 | Phillips | 48 38 00 N | 107 15 53 W |
| Garrison Spring | Spring | 1949 | Madison | 45 29 58 N | 112 35 11 W |
| Garrit Schoolhouse Coulee | Valley | | Phillips | 47 35 40 N | 108 08 09 W |
| Garrity Mountain | Summit | 2452 | Deer Lodge | 46 08 46 N | 113 05 24 W |
| Garrow Ranch | Locale | 1290 | Lewis and Clark | 47 05 20 N | 112 09 29 W |
| Garry Lookout Tower | Tower | 1371 | Flathead | 48 24 33 N | 113 44 02 W |
| Garry Post Office (historical) | Post Office | 1082 | Flathead | 48 23 60 N | 113 42 43 W |
| Garryowen | Populated Place | 951 | Big Horn | 45 31 36 N | 107 25 10 W |
| Garryowen (historical) | Locale | 951 | Big Horn | 45 31 35 N | 107 25 10 W |
| Garryowen Historical Marker | Park | 948 | Big Horn | 45 31 40 N | 107 25 09 W |
| Garryowen Mission School (historical) | School | 969 | Big Horn | 45 31 40 N | 107 25 52 W |
| Garryowen Post Office | Post Office | 951 | Big Horn | 45 31 35 N | 107 25 10 W |
| Garst Creek | Stream | | Powder River | 45 10 41 N | 105 46 24 W |
| Garton Coulee | Valley | | McCone | 47 47 58 N | 105 45 12 W |
| Gartside Dam | Dam | 606 | Richland | 47 35 06 N | 104 16 14 W |
| Gartside Lake | Reservoir | 606 | Richland | 47 35 06 N | 104 16 14 W |
| Gartside Reservoir | Reservoir | 610 | Richland | 47 35 07 N | 104 16 17 W |
| Gartside Reservoir Fishing Access Site | Locale | 603 | Richland | 47 35 01 N | 104 16 19 W |
| Garver Creek | Stream | | Lincoln | 48 59 05 N | 115 49 20 W |
| Garver Creek Snow Gage | Locale | 1295 | Lincoln | 48 58 30 N | 115 49 09 W |
| Garver Mountain | Summit | 1785 | Lincoln | 48 55 45 N | 115 47 41 W |
| Garver Mountain Lookout Tower | Tower | 1790 | Lincoln | 48 55 45 N | 115 47 43 W |
| Garverich Number 1 Dam | Dam | 827 | Treasure | 46 14 36 N | 107 07 56 W |
| Garverich Ranch | Locale | 825 | Treasure | 46 14 18 N | 107 08 23 W |
| Garverich Spring | Spring | 983 | Treasure | 46 09 37 N | 107 13 16 W |
| Garvin Basin | Basin | 1446 | Big Horn | 45 02 56 N | 108 09 01 W |
| Garvin School (historical) | School | 767 | Prairie | 46 50 23 N | 104 56 37 W |
| Gary (historical) | Locale | 1041 | Cascade | 47 08 30 N | 111 51 38 W |
| Gary Post Office (historical) | Post Office | 1041 | Cascade | 47 08 30 N | 111 51 38 W |
| Gary Smith Memorial | Locale | 1142 | Glacier | 48 38 34 N | 112 20 03 W |
| Gas City Oil Field | Oilfield | 661 | Dawson | 46 55 16 N | 104 44 17 W |
| Gash Creek | Stream | | Ravalli | 46 24 38 N | 114 11 33 W |
| Gash Point | Summit | 2664 | Ravalli | 46 26 01 N | 114 19 11 W |
| Gaskill Creek | Stream | | Granite | 46 33 49 N | 113 08 38 W |
| Gaskill Creek | Stream | | Powder River | 45 44 04 N | 105 52 42 W |
| Gaskill Reservoir | Reservoir | 1018 | Powder River | 45 35 17 N | 106 04 26 W |
| Gaskill Reservoir | Reservoir | 976 | Powder River | 45 35 36 N | 106 07 21 W |
| Gasoway (historical) | Locale | 1708 | Park | 45 33 25 N | 110 45 13 W |
| Gasparage Spring | Spring | 1110 | Chouteau | 48 00 22 N | 109 35 46 W |
| Gaspard (historical) | Locale | 938 | Missoula | 46 57 10 N | 114 10 53 W |
| Gass Flat | Flat | 1029 | Treasure | 45 59 18 N | 107 16 20 W |
| Gass Reservoir | Reservoir | 692 | McCone | 47 45 21 N | 105 51 20 W |
| Gass Reservoir Dam | Dam | 621 | McCone | 48 00 30 N | 105 49 56 W |
| Gate Coulee | Valley | | Prairie | 46 43 47 N | 105 27 17 W |
| Gate Creek | Stream | | Powder River | 45 21 01 N | 106 08 49 W |
| Gate Creek | Stream | | Rosebud | 45 26 51 N | 106 23 52 W |
| Gate Creek Spring | Spring | 1081 | Rosebud | 45 24 34 N | 106 21 42 W |
| Gate Creek Spring Number One | Spring | 1030 | Powder River | 45 20 37 N | 106 10 41 W |
| Gate Creek Spring Number Two | Spring | 1070 | Powder River | 45 20 24 N | 106 11 17 W |
| Gate Lake | Lake | 1808 | Park | 45 38 17 N | 110 20 31 W |
| Gates Creek | Stream | | Lewis and Clark | 47 46 57 N | 112 55 19 W |
| Gates Lake | Lake | 1631 | Lewis and Clark | 47 46 58 N | 112 56 28 W |
| Gates of the Mountains and the Bear Tooth Historical Marker (historical) | Park | 1217 | Lewis and Clark | 46 49 14 N | 112 00 05 W |
| Gates of the Mountains Boat Club | Locale | 1092 | Lewis and Clark | 46 49 56 N | 111 56 57 W |
| Gates of the Mountains Game Preserve | Park | 1336 | Lewis and Clark | 46 51 34 N | 111 55 03 W |
| Gates of the Mountains Wilderness | Reserve | 1847 | Lewis and Clark | 46 52 12 N | 111 48 47 W |
| Gates of the Rocky Mountains | Gap | 1093 | Lewis and Clark | 46 52 37 N | 111 54 50 W |
| Gates Park | Flat | 1629 | Lewis and Clark | 47 47 40 N | 112 56 36 W |
| Gates Park Guard Station | Locale | 1624 | Lewis and Clark | 47 47 23 N | 112 56 25 W |
| Gates Post Office (historical) | Post Office | 1055 | Toole | 48 15 22 N | 111 30 53 W |
| Gateway (historical) | Locale | 751 | Lincoln | 48 59 57 N | 115 10 24 W |
| Gateway (historical) | Populated Place | 751 | Lincoln | 48 59 57 N | 115 10 24 W |
| Gateway Baptist Church | Church | 1694 | Carbon | 45 11 15 N | 109 14 48 W |
| Gateway Baptist Church | Church | 1158 | Lewis and Clark | 46 37 38 N | 112 01 18 W |
| Gateway Bible Church | Church | 1501 | Gallatin | 45 35 33 N | 111 12 11 W |
| Gateway Bridges | Bridge | 1499 | Gallatin | 45 35 28 N | 111 12 48 W |
| Gateway Cabin | Locale | 1867 | Flathead | 48 03 30 N | 112 59 08 W |
| Gateway Campground | Locale | 757 | Lincoln | 48 59 52 N | 115 09 55 W |