Feature Name | Class | Elev. meters | County | Latitude DMS | Longitude DMS |
| Jefferson City Post Office | Post Office | 1391 | Jefferson | 46 23 18 N | 112 01 39 W |
| Jefferson City Rest Area | Locale | 1366 | Jefferson | 46 24 20 N | 112 00 43 W |
| Jefferson County | Civil | 1664 | Jefferson | 46 11 00 N | 112 10 03 W |
| Jefferson County Courthouse | Building | 1737 | Jefferson | 46 09 10 N | 112 07 18 W |
| Jefferson County Sheriffs Office | Building | 1496 | Jefferson | 46 14 12 N | 112 07 15 W |
| Jefferson Creek | Stream | | Cascade | 46 54 31 N | 110 41 23 W |
| Jefferson Creek | Stream | | Flathead | 48 54 48 N | 114 05 41 W |
| Jefferson Creek | Stream | | Powell | 46 46 21 N | 112 44 49 W |
| Jefferson Creek | Stream | | Teton | 47 48 17 N | 112 34 51 W |
| Jefferson Elementary School | School | 1266 | Lewis and Clark | 46 35 02 N | 112 01 21 W |
| Jefferson Gulch (historical) | Locale | 1410 | Powell | 46 46 60 N | 112 46 33 W |
| Jefferson High School | School | 1494 | Jefferson | 46 14 02 N | 112 07 11 W |
| Jefferson Island | Populated Place | 1304 | Madison | 45 51 03 N | 111 56 26 W |
| Jefferson Island (historical) | Locale | 1304 | Madison | 45 51 03 N | 111 56 26 W |
| Jefferson Island Post Office (historical) | Post Office | 1304 | Madison | 45 51 03 N | 111 56 26 W |
| Jefferson Meadows | Flat | 1190 | Sanders | 47 53 13 N | 115 11 12 W |
| Jefferson Mount | Summit | 3071 | Beaverhead | 44 33 45 N | 111 30 17 W |
| Jefferson Pass | Gap | 1998 | Glacier | 48 53 45 N | 114 02 15 W |
| Jefferson Point | Cape | 622 | Valley | 48 03 49 N | 106 24 03 W |
| Jefferson River | Stream | | Gallatin | 45 55 39 N | 111 30 29 W |
| Jefferson River Bridge | Bridge | 1238 | Gallatin | 45 54 51 N | 111 32 34 W |
| Jefferson River Camp | Locale | 1395 | Madison | 45 40 37 N | 112 17 33 W |
| Jefferson School | School | 723 | Custer | 46 24 35 N | 105 49 56 W |
| Jefferson School | School | 646 | Dawson | 47 06 32 N | 104 44 52 W |
| Jefferson School | School | 970 | Missoula | 46 50 60 N | 114 01 20 W |
| Jefferson School (historical) | School | 653 | Dawson | 47 06 55 N | 104 45 54 W |
| Jefferson School (historical) | School | 1274 | Jefferson | 45 49 42 N | 111 42 08 W |
| Jefferson School (historical) | School | 1088 | Ravalli | 46 14 23 N | 114 09 41 W |
| Jefferson School (historical) | School | 647 | Sheridan | 48 48 13 N | 104 08 09 W |
| Jefferson Slough | Stream | | Jefferson | 45 51 27 N | 111 55 48 W |
| Jefferson Valley Baptist Church | Church | 1329 | Jefferson | 45 52 15 N | 112 05 51 W |
| Jefferson Valley Historical Marker | Park | 1391 | Madison | 45 37 16 N | 112 18 38 W |
| Jefferson Valley Museum | Building | 1329 | Jefferson | 45 52 15 N | 112 05 51 W |
| Jeffrey Ditch | Canal | 1621 | Carbon | 45 15 17 N | 109 11 06 W |
| Jeffrey Number 1 Dam | Dam | 723 | Garfield | 47 19 24 N | 106 21 38 W |
| Jeffrey Number 2 Dam | Dam | 760 | Garfield | 47 17 06 N | 106 17 02 W |
| Jeffries Creek | Stream | | Lewis and Clark | 47 10 07 N | 112 12 42 W |
| Jeffries Mine | Mine | 1110 | Musselshell | 46 23 38 N | 108 28 47 W |
| Jeffrys Prong | Stream | | Rosebud | 45 17 51 N | 106 41 42 W |
| Jehovah Lutheran Cemetery | Cemetery | 686 | Dawson | 46 52 58 N | 104 55 53 W |
| Jehovah Witnesses Kingdom Hall | Church | 999 | Ravalli | 46 36 45 N | 114 05 23 W |
| Jehovah's Witness | Church | 640 | Dawson | 47 06 18 N | 104 45 19 W |
| Jehovah's Witness Kingdom Hall | Church | 839 | Mineral | 47 11 20 N | 114 52 55 W |
| Jehovah's Witnesses | Church | 723 | Custer | 46 24 34 N | 105 50 00 W |
| Jehovah's Witnesses | Church | 915 | Fallon | 46 21 37 N | 104 16 53 W |
| Jehovah's Witnesses | Church | 1377 | Gallatin | 45 45 08 N | 111 10 58 W |
| Jehovah's Witnesses | Church | 1148 | Glacier | 48 38 20 N | 112 20 14 W |
| Jehovah's Witnesses | Church | 793 | Hill | 48 32 20 N | 109 41 33 W |
| Jehovah's Witnesses | Church | 603 | Richland | 47 43 10 N | 104 11 15 W |
| Jehovah's Witnesses | Church | 640 | Roosevelt | 48 06 07 N | 105 38 54 W |
| Jehovah's Witnesses | Church | 769 | Rosebud | 46 15 53 N | 106 40 55 W |
| Jehovah's Witnesses | Church | 1093 | Stillwater | 45 38 12 N | 109 15 08 W |
| Jehovah's Witnesses | Church | 1005 | Toole | 48 30 19 N | 111 51 25 W |
| Jehovah's Witnesses | Church | 645 | Valley | 48 12 00 N | 106 37 58 W |
| Jehovahs Witnesses | Church | 918 | Flathead | 48 14 25 N | 114 17 53 W |
| Jehovahs Witnesses | Church | 936 | Flathead | 48 22 05 N | 114 12 03 W |
| Jehovahs Witnesses | Church | 893 | Flathead | 48 03 49 N | 114 04 53 W |
| Jehovahs Witnesses | Church | 1012 | Lake | 47 40 25 N | 114 06 43 W |
| Jehovahs Witnesses | Church | 1186 | Lewis and Clark | 46 36 35 N | 112 01 03 W |
| Jehovahs Witnesses | Church | 787 | Lincoln | 48 52 48 N | 115 03 13 W |
| Jehovahs Witnesses | Church | 1558 | Meagher | 46 32 36 N | 110 53 58 W |
| Jehovahs Witnesses | Church | 971 | Missoula | 46 49 40 N | 114 02 23 W |
| Jehovahs Witnesses | Church | 1392 | Powell | 46 23 45 N | 112 43 48 W |
| Jehovahs Witnesses | Church | 790 | Sanders | 47 35 55 N | 115 20 14 W |
| Jehovahs Witnesses Kingdom Hall | Church | 1093 | Ravalli | 46 13 54 N | 114 09 33 W |
| Jehovahs Witnesses North and East Congregation | Church | 1050 | Cascade | 47 30 45 N | 111 14 23 W |
| Jellison Place | Populated Place | 1781 | Wheatland | 46 40 24 N | 110 04 20 W |
| Jellison Reservoir | Reservoir | 1712 | Wheatland | 46 39 42 N | 110 03 43 W |
| Jello Dam | Dam | 1066 | Carter | 45 02 06 N | 104 19 56 W |
| Jelly Bean Dam | Dam | 1009 | Fergus | 47 07 24 N | 108 46 39 W |
| Jellystone RV Park | Locale | 977 | Missoula | 46 56 38 N | 114 07 38 W |
| Jenkins Creek | Stream | | Powder River | 45 06 23 N | 105 50 25 W |
| Jenkins Gulch | Valley | | Broadwater | 46 18 03 N | 111 44 12 W |
| Jenkins Gulch Creek | Stream | | Broadwater | 46 18 03 N | 111 44 06 W |
| Jenkins Ridge | Ridge | 1956 | Granite | 46 32 18 N | 113 25 03 W |
| Jenks (historical) | Locale | 589 | Richland | 47 39 26 N | 104 12 03 W |
| Jennaway Number 1 Dam | Dam | 895 | Musselshell | 46 36 42 N | 107 52 26 W |
| Jenni School (historical) | School | 1216 | Fergus | 47 03 20 N | 109 34 35 W |
| Jennie Whipple Mine | Mine | 2299 | Cascade | 46 56 44 N | 110 42 15 W |
| Jennie Whipple Number 2 Mine | Mine | 2328 | Cascade | 46 56 42 N | 110 42 18 W |
| Jennie Whipple Number 3 Mine | Mine | 2394 | Cascade | 46 56 36 N | 110 42 18 W |
| Jennies Fork | Stream | | Lewis and Clark | 46 45 10 N | 112 17 40 W |
| Jennings | Populated Place | 643 | Lincoln | 48 21 56 N | 115 20 41 W |
| Jennings (historical) | Locale | 1128 | Carbon | 45 14 57 N | 108 56 18 W |
| Jennings (historical) | Locale | 643 | Lincoln | 48 21 56 N | 115 20 41 W |
| Jennings (historical) | Locale | 1013 | Missoula | 46 50 15 N | 113 49 53 W |
| Jennings Camp Creek | Stream | | Ravalli | 45 53 31 N | 113 49 52 W |
| Jennings Campground | Locale | 1490 | Ravalli | 45 53 47 N | 113 49 10 W |
| Jennings Post Office (historical) | Post Office | 643 | Lincoln | 48 21 56 N | 115 20 41 W |
| Jennings Ranch | Locale | 931 | Sanders | 47 28 44 N | 114 29 22 W |
| Jennings School (historical) | School | 643 | Lincoln | 48 21 56 N | 115 20 41 W |
| Jenny Creek | Stream | | Powell | 47 17 53 N | 113 17 41 W |
| Jenny Lake | Lake | 2859 | Carbon | 45 01 58 N | 109 44 27 W |
| Jenny Lake | Lake | 1997 | Flathead | 48 16 39 N | 114 05 03 W |
| Jens | Locale | 1263 | Powell | 46 36 15 N | 113 00 22 W |
| Jens | Populated Place | 1263 | Powell | 46 36 15 N | 113 00 22 W |
| Jens Post Office (historical) | Post Office | 1263 | Powell | 46 36 15 N | 113 00 22 W |
| Jens School (historical) | School | 1263 | Powell | 46 36 15 N | 113 00 22 W |
| Jensen Coulee | Valley | | Pondera | 48 09 26 N | 112 25 34 W |
| Jensen Coulee | Valley | | Valley | 48 44 47 N | 107 00 53 W |
| Jensen Creek | Stream | | Beaverhead | 45 03 29 N | 113 16 42 W |
| Jensen Dam | Dam | 861 | Garfield | 47 30 00 N | 106 45 02 W |
| Jensen Elevator | Locale | 1084 | Teton | 47 51 15 N | 111 29 30 W |
| Jensen Number 2 Dam | Dam | 747 | Dawson | 47 28 48 N | 105 20 26 W |
| Jensen Number 3 Dam | Dam | 821 | Dawson | 47 22 48 N | 105 20 02 W |
| Jensen Ranch | Locale | 1484 | Gallatin | 46 07 07 N | 111 00 55 W |
| Jensen Ranch | Locale | 1342 | Teton | 48 05 56 N | 112 28 58 W |
| Jensen Reservoir Dam | Dam | 773 | Dawson | 47 27 06 N | 105 17 50 W |
| Jensen Spring | Spring | 1552 | Chouteau | 47 29 06 N | 110 25 48 W |
| Jericho (historical) | Locale | 1668 | Cascade | 46 57 06 N | 110 45 08 W |