| Name | What | Region | Country | Lat | Long | Elev ft. | Pop est |
|---|---|---|---|---|---|---|---|
| Labelle | city | Idaho | United States | 43.70 | -111.86 | 5029 | |
| Laclede | city | Idaho | United States | 48.17 | -116.76 | 2060 | |
| Lacon | city | Idaho | United States | 47.44 | -116.75 | 2598 | |
| Lago | city | Idaho | United States | 42.45 | -111.70 | 5127 | |
| Lake | city | Idaho | United States | 44.67 | -111.39 | 6709 | |
| Lake Fork | city | Idaho | United States | 44.83 | -116.08 | 5029 | |
| Lakeshore Summer Home Area | city | Idaho | United States | 44.65 | -115.66 | 5869 | |
| Lakeview | city | Idaho | United States | 47.97 | -116.45 | 2509 | |
| Lamb Creek | city | Idaho | United States | 48.52 | -116.93 | 2598 | |
| Lamont | city | Idaho | United States | 43.97 | -111.22 | 6000 | |
| Lanark | city | Idaho | United States | 42.28 | -111.43 | 5980 | |
| Landmark | city | Idaho | United States | 44.66 | -115.55 | 6791 | |
| Landore | city | Idaho | United States | 45.12 | -116.63 | 6194 | |
| Lane | city | Idaho | United States | 47.51 | -116.54 | 2509 | |
| Lapwai | city | Idaho | United States | 46.40 | -116.80 | 1000 | |
| Larson | city | Idaho | United States | 47.47 | -115.75 | 4189 | |
| Last Chance | city | Idaho | United States | 44.37 | -111.40 | 6174 | |
| Lava Hot Springs | city | Idaho | United States | 42.62 | -112.01 | 5997 | |
| Lawman Ford | city | Idaho | United States | 45.11 | -115.61 | 4189 | |
| Leadore | city | Idaho | United States | 44.68 | -113.36 | 5974 | |
| Leadville | city | Idaho | United States | 44.71 | -113.31 | 6709 | |
| Leduc (historical) | city | Idaho | United States | 43.33 | -114.07 | 5029 | |
| Leesburg | city | Idaho | United States | 45.22 | -114.11 | 6709 | |
| Leland | city | Idaho | United States | 46.58 | -116.61 | 2509 | |
| Lemhi | city | Idaho | United States | 44.85 | -113.62 | 5259 | |
| Len Landing | city | Idaho | United States | 47.53 | -116.84 | 2509 | |
| Lenore | city | Idaho | United States | 46.51 | -116.55 | 1095 | |
| Lenville | city | Idaho | United States | 46.64 | -116.84 | 2509 | |
| Leon | city | Idaho | United States | 46.53 | -117.04 | 2598 | |
| Leone | city | Idaho | United States | 43.41 | -116.09 | 3349 | |
| Leonia | city | Idaho | United States | 48.62 | -116.05 | 1797 | |
| Leprouse | city | Idaho | United States | 45.74 | -115.39 | 4399 | |
| Leslie | city | Idaho | United States | 43.87 | -113.47 | 5869 | |
| Letha | city | Idaho | United States | 43.89 | -116.65 | 2509 | |
| Level (historical) | city | Idaho | United States | 43.90 | -112.49 | 5029 | |
| Lewiston | city | Idaho | United States | 46.42 | -117.02 | 830 | |
| Lewiston Orchards | city | Idaho | United States | 46.38 | -116.98 | 1669 | |
| Lewisville | city | Idaho | United States | 43.70 | -112.01 | 5029 | |
| Liberty | city | Idaho | United States | 43.17 | -112.56 | 4445 | |
| Liberty | city | Idaho | United States | 42.32 | -111.45 | 5990 | |
| Lidy Hot Springs | city | Idaho | United States | 44.13 | -112.55 | 5029 | |
| Lidyville (historical) | city | Idaho | United States | 46.60 | -116.80 | 2509 | |
| Lifton | city | Idaho | United States | 42.12 | -111.31 | 5921 | |
| Lightfoot | city | Idaho | United States | 45.72 | -115.36 | 4399 | |
| Lignite | city | Idaho | United States | 48.23 | -116.54 | 2509 | |
| Lincoln | city | Idaho | United States | 43.51 | -111.96 | 5029 | |
| Linden | city | Idaho | United States | 46.67 | -116.50 | 3349 | |
| Lindsayville | city | Idaho | United States | 42.43 | -111.42 | 5997 | |
| Linfor | city | Idaho | United States | 47.61 | -116.24 | 2509 | |
| Little Rock | city | Idaho | United States | 43.92 | -116.69 | 2509 | |
| Little Sugar Loaf | city | Idaho | United States | 43.10 | -116.70 | 6223 | |
| Lodi (historical) | city | Idaho | United States | 44.09 | -111.46 | 5223 | |
| Lone Pine | city | Idaho | United States | 44.19 | -112.94 | 6145 | |
| Lone Rock | city | Idaho | United States | 42.77 | -112.82 | 5029 | |
| Long Creek Summit Home | city | Idaho | United States | 44.13 | -115.58 | 5390 | |
| Lorenzo | city | Idaho | United States | 43.73 | -111.87 | 5029 | |
| Lost River | city | Idaho | United States | 43.69 | -113.37 | 5869 | |
| Lost River | city | Idaho | United States | 43.69 | -113.61 | 6161 | |
| Lotus | city | Idaho | United States | 47.23 | -116.62 | 2509 | |
| Lowell | city | Idaho | United States | 46.14 | -115.60 | 1742 | |
| Lower Stanley | city | Idaho | United States | 44.23 | -114.93 | 6709 | |
| Lowman | city | Idaho | United States | 44.08 | -115.62 | 4189 | |
| Lucile | city | Idaho | United States | 45.54 | -116.31 | 1797 | |
| Lund | city | Idaho | United States | 42.64 | -111.89 | 5869 | |
| Lyman | city | Idaho | United States | 43.74 | -111.82 | 5029 | |
| Lyondale (historical) | city | Idaho | United States | 47.61 | -116.85 | 2509 |