19 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Ontonagon | 1 | 2,265 | 2,253 | -0.44% | 12 | 194 | Township |
| Ontonagon | 2 | 1,262 | 1,261 | 0% | 342 | 4 | Village |
| Stannard | 3 | 636 | 642 | -0.78% | 5 | 125 | Township |
| Greenland | 4 | 625 | 632 | -0.64% | 6 | 113 | Township |
| Bergland | 5 | 438 | 436 | -0.23% | 4 | 97 | Township |
| McMillan | 6 | 401 | 407 | -0.99% | 6 | 71 | Township |
| White Pine | 7 | 400 | 446 | -1.23% | 80 | 5 | CDP |
| Ewen | 8 | 379 | 267 | 7.06% | 450 | 1 | CDP |
| Bruce Crossing | 9 | 321 | 347 | 7% | 71 | 5 | CDP |
| Interior | 10 | 265 | 269 | -1.12% | 3 | 86 | Township |
| Rockland | 11 | 242 | 207 | 7.08% | 549 | 0 | CDP |
| Mass City | 12 | 224 | 170 | 7.18% | 416 | 1 | CDP |
| Rockland | 13 | 224 | 222 | 0% | 2 | 93 | Township |
| Haight | 14 | 205 | 206 | -0.49% | 2 | 106 | Township |
| Greenland | 15 | 161 | 124 | 7.33% | 391 | 0 | CDP |
| Lake Gogebic | 16 | 146 | 129 | 7.35% | 135 | 1 | CDP |
| Bergland | 17 | 139 | 111 | 6.92% | 190 | 1 | CDP |
| Matchwood | 18 | 81 | 82 | -1.22% | 1 | 109 | Township |
| Bohemia | 19 | 71 | 72 | -1.39% | 1 | 92 | Township |
Ontonagon is the largest city in Ontonagon County, with a population of 2,265.
Bohemia is the smallest city in Ontonagon County, with a population of 71.
There are 19 cities in Ontonagon County, Michigan.