Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| MacLean Creek | Stream | | Silver Bow | 45 44 35 N | 112 40 19 W |
| MacLess (historical) | Locale | 1295 | Gallatin | 45 51 38 N | 111 16 19 W |
| Macmeal Ridge | Ridge | 1489 | Blaine | 47 56 55 N | 108 39 37 W |
| Macnab Campground | Locale | 1073 | Carter | 45 50 06 N | 104 26 02 W |
| Macon | Locale | 604 | Roosevelt | 48 06 35 N | 105 31 08 W |
| Macon | Populated Place | 604 | Roosevelt | 48 06 35 N | 105 31 08 W |
| Macon School (historical) | School | 604 | Roosevelt | 48 06 48 N | 105 30 09 W |
| Macs Draw | Valley | | Powder River | 45 05 20 N | 106 03 43 W |
| Macs Museum | Building | 924 | Powder River | 45 26 43 N | 105 24 31 W |
| Mad Chant Dam | Dam | 1711 | Madison | 45 20 30 N | 112 19 09 W |
| Mad Dam | Dam | 1377 | Judith Basin | 47 21 12 N | 110 33 57 W |
| Mad Wolf Mountain | Summit | 2538 | Glacier | 48 34 04 N | 113 22 07 W |
| Mad Wolf Ski Trail | Trail | 2365 | Madison | 45 16 51 N | 111 24 24 W |
| Madden Lake | Lake | 866 | Lincoln | 48 52 59 N | 115 08 13 W |
| Madden School (historical) | School | 1208 | Cascade | 47 34 54 N | 111 52 28 W |
| Maddios Hairstyling and Cosmetology College | School | 1233 | Lewis and Clark | 46 35 35 N | 112 02 13 W |
| Maddox Hole | Bend | 1581 | Beaverhead | 45 37 46 N | 112 41 31 W |
| Maddox Ranch Corporation Number 1 Dam | Dam | 741 | Blaine | 48 36 42 N | 109 15 39 W |
| Maddox School (historical) | School | 1223 | Fergus | 46 58 55 N | 108 49 18 W |
| Maddux | Populated Place | 1370 | Blaine | 48 08 26 N | 109 25 05 W |
| Maddux Post Office (historical) | Post Office | 1276 | Blaine | 48 07 18 N | 109 22 58 W |
| Maddux School (historical) | School | 1411 | Blaine | 48 08 52 N | 109 22 57 W |
| Madge Creek | Stream | | Lincoln | 48 19 17 N | 115 49 23 W |
| Madigan Gulch | Valley | | Beaverhead | 45 08 13 N | 112 57 04 W |
| Madison Arm | Bay | 1993 | Gallatin | 44 43 57 N | 111 08 56 W |
| Madison Arm Resort | Locale | 1995 | Gallatin | 44 44 07 N | 111 11 08 W |
| Madison Avenue Ski Trail | Trail | 2365 | Madison | 45 16 51 N | 111 24 24 W |
| Madison Buffalo Jump State Monument | Park | 1388 | Gallatin | 45 47 40 N | 111 27 45 W |
| Madison Campground | Locale | 1793 | Madison | 44 53 13 N | 111 34 56 W |
| Madison County | Civil | 2178 | Madison | 45 17 00 N | 111 52 03 W |
| Madison County Courthouse | Building | 1772 | Madison | 45 17 36 N | 111 56 41 W |
| Madison County Fairgrounds | Locale | 1413 | Madison | 45 32 30 N | 112 20 08 W |
| Madison County Nursing Home | Hospital | 1507 | Madison | 45 21 08 N | 111 43 54 W |
| Madison County Sheriffs Office | Building | 1772 | Madison | 45 17 36 N | 111 56 41 W |
| Madison Creek | Stream | | Powell | 47 07 35 N | 112 58 29 W |
| Madison Dam | Dam | 1686 | Madison | 45 28 12 N | 111 39 15 W |
| Madison Dike | Levee | 1255 | Gallatin | 45 51 09 N | 111 29 34 W |
| Madison Grade | Summit | 1350 | Stillwater | 45 30 59 N | 109 36 27 W |
| Madison Gulch | Valley | | Missoula | 46 57 20 N | 114 25 58 W |
| Madison Gulch | Valley | | Powell | 46 47 41 N | 112 42 48 W |
| Madison Meadow | Swamp | 1337 | Powell | 47 03 57 N | 112 54 23 W |
| Madison Meadows Golf Course | Locale | 1531 | Madison | 45 21 25 N | 111 44 55 W |
| Madison Mine | Mine | 2187 | Beaverhead | 45 18 40 N | 112 53 09 W |
| Madison Park | Park | 1031 | Cascade | 47 31 38 N | 111 18 51 W |
| Madison Park | Park | 977 | Missoula | 46 51 56 N | 113 59 09 W |
| Madison Plateau | Plain | 2241 | Gallatin | 44 36 60 N | 111 01 03 W |
| Madison Plateau | Plain | 1571 | Gallatin | 45 42 26 N | 111 26 27 W |
| Madison Post Office (historical) | Post Office | 1237 | Gallatin | 45 54 30 N | 111 31 53 W |
| Madison Powerhouse | Locale | 1442 | Madison | 45 29 16 N | 111 38 05 W |
| Madison Range | Range | 2837 | Madison | 45 14 60 N | 111 30 03 W |
| Madison River | Stream | | Gallatin | 45 55 39 N | 111 30 29 W |
| Madison River Bridge | Bridge | 1996 | Gallatin | 44 42 57 N | 111 06 10 W |
| Madison River Bridge | Bridge | 1356 | Madison | 45 36 25 N | 111 34 27 W |
| Madison River Lodge | Locale | 1837 | Madison | 44 51 24 N | 111 32 40 W |
| Madison Side | Slope | 1989 | Madison | 44 49 35 N | 111 25 38 W |
| Madison Slide | Valley | 1962 | Madison | 44 49 42 N | 111 25 38 W |
| Madison Valley | Valley | | Gallatin | 44 43 50 N | 111 12 28 W |
| Madison Valley Baptist Church | Church | 1506 | Madison | 45 20 56 N | 111 43 47 W |
| Madison Valley Cemetery | Cemetery | 1515 | Madison | 45 20 02 N | 111 42 20 W |
| Madison Valley Clinic | Hospital | 1513 | Madison | 45 21 04 N | 111 43 55 W |
| Madison Valley Hospital | Hospital | 1512 | Madison | 45 21 05 N | 111 43 54 W |
| Madison Valley Presbyterian Church | Church | 1569 | Madison | 45 20 48 N | 111 45 02 W |
| Madison Valley Public Library | Building | 1513 | Madison | 45 20 60 N | 111 43 59 W |
| Madman Coulee | Valley | | Glacier | 48 40 47 N | 113 14 56 W |
| Madoc | Locale | 847 | Daniels | 48 48 43 N | 105 17 08 W |
| Madoc | Populated Place | 847 | Daniels | 48 48 39 N | 105 17 09 W |
| Madoc Elevator (historical) | Locale | 847 | Daniels | 48 48 45 N | 105 17 07 W |
| Madoc Post Office (historical) | Post Office | 847 | Daniels | 48 48 39 N | 105 17 09 W |
| Madoc School (historical) | School | 847 | Daniels | 48 48 39 N | 105 17 09 W |
| Madras School (historical) | School | 720 | Blaine | 48 33 14 N | 108 52 43 W |
| Magdalen (historical) | Locale | 2021 | Beaverhead | 44 36 50 N | 111 45 23 W |
| Magdalen Post Office (historical) | Post Office | 2021 | Beaverhead | 44 36 50 N | 111 45 23 W |
| Magee Cemetery | Cemetery | 1542 | Park | 45 23 56 N | 110 36 25 W |
| Magee Creek | Stream | | Park | 45 23 51 N | 110 36 21 W |
| Magee Ditch | Canal | 1356 | Stillwater | 45 29 30 N | 109 33 29 W |
| Magee Lake | Lake | 1426 | Glacier | 48 28 12 N | 112 57 53 W |
| Magee Ranch | Locale | 1263 | Glacier | 48 25 37 N | 112 58 22 W |
| Magee Spring | Spring | 2695 | Beaverhead | 44 36 38 N | 112 43 25 W |
| Maggie Anderson School (historical) | School | 980 | Treasure | 46 01 39 N | 107 11 30 W |
| Maggie Creek | Stream | | Blaine | 48 16 53 N | 108 55 52 W |
| Maggie Creek | Stream | | Custer | 46 00 20 N | 105 35 37 W |
| Maggie Creek | Stream | | Custer | 46 32 58 N | 105 20 12 W |
| Maggie Creek | Stream | | Flathead | 48 17 29 N | 113 56 26 W |
| Maggie Draw | Valley | | Wibaux | 46 49 35 N | 104 34 34 W |
| Maggot Spring | Spring | 2352 | Jefferson | 46 03 55 N | 112 01 58 W |
| Maginnis Creek | Stream | | Petroleum | 46 47 35 N | 107 58 13 W |
| Maginnis Mine | Mine | 1556 | Fergus | 47 10 25 N | 109 13 52 W |
| Maginnis Mountain | Summit | 1770 | Fergus | 47 12 54 N | 109 10 18 W |
| Magna Charta Mine | Mine | 1931 | Silver Bow | 46 02 06 N | 112 32 05 W |
| Magna Mine | Mine | 2630 | Beaverhead | 45 27 14 N | 113 03 20 W |
| Magna Mine | Mine | 2597 | Beaverhead | 45 27 12 N | 113 03 21 W |
| Magnesia Creek | Stream | | Flathead | 48 38 49 N | 114 52 53 W |
| Magnesia Dam | Dam | 858 | Garfield | 47 02 60 N | 106 43 08 W |
| Magnolia Post Office (historical) | Post Office | 1155 | Broadwater | 46 28 13 N | 111 33 13 W |
| Magnum East Dam | Dam | 876 | Hill | 48 41 06 N | 110 22 09 W |
| Magnum South Dam | Dam | 876 | Hill | 48 41 12 N | 110 22 09 W |
| Magone and Anderson Mine | Mine | 1893 | Granite | 46 49 13 N | 113 20 06 W |
| Magone Mountain | Summit | | Mineral | 47 06 31 N | 114 51 10 W |
| Magpie (historical) | Locale | 1170 | Lewis and Clark | 46 38 45 N | 111 40 53 W |
| Magpie Canyon | Valley | | Stillwater | 45 27 49 N | 109 44 56 W |
| Magpie Coulee | Valley | | Rosebud | 46 51 20 N | 106 55 15 W |
| Magpie Coulee | Valley | | Yellowstone | 45 35 01 N | 108 24 23 W |
| Magpie Creek | Stream | | Dawson | 46 55 46 N | 104 44 30 W |
| Magpie Creek | Stream | | Lewis and Clark | 46 38 17 N | 111 41 32 W |
| Magpie Creek | Stream | | Madison | 45 39 56 N | 111 53 10 W |
| Magpie Creek | Stream | | Powder River | 45 33 14 N | 105 19 29 W |
| Magpie Creek | Stream | | Sanders | 47 19 49 N | 114 28 31 W |
| Magpie Creek | Stream | | Stillwater | 45 27 55 N | 109 45 03 W |
| Magpie Gulch | Valley | | Beaverhead | 44 59 22 N | 113 19 44 W |
| Magpie Rapids | Rapids | 711 | Blaine | 47 47 35 N | 109 12 58 W |