33 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mayville | 1 | 1,777 | 1,846 | -0.78% | 943 | 1.88 | City |
| Hillsboro | 2 | 1,636 | 1,648 | -0.12% | 1,471 | 1.11 | City |
| Hatton | 3 | 693 | 715 | -0.57% | 1,242 | 0.56 | City |
| Portland | 4 | 573 | 582 | -0.35% | 687 | 0.83 | City |
| Buxton | 5 | 349 | 348 | 0% | 1,045 | 0.33 | City |
| Viking township | 6 | 170 | 166 | -0.58% | 5 | 34.83 | Township |
| Ervin township | 7 | 169 | 168 | -0.59% | 5 | 36.40 | Township |
| Garfield township | 8 | 167 | 173 | -0.6% | 5 | 34.98 | Township |
| Norway township | 9 | 160 | 163 | -0.62% | 4 | 35.70 | Township |
| Bloomfield township | 10 | 133 | 137 | -0.75% | 4 | 36.06 | Township |
| Wold township | 11 | 121 | 122 | -0.82% | 3 | 35.85 | Township |
| Eldorado township | 12 | 113 | 112 | -0.88% | 3 | 35.80 | Township |
| Caledonia township | 13 | 111 | 115 | -0.89% | 4 | 29.54 | Township |
| Galesburg | 14 | 110 | 115 | -0.9% | 667 | 0.17 | City |
| Hillsboro township | 15 | 107 | 111 | -0.93% | 3 | 34.80 | Township |
| Mayville township | 16 | 107 | 111 | -0.93% | 3 | 34.95 | Township |
| Buxton township | 17 | 106 | 107 | 0% | 3 | 34.88 | Township |
| Stavanger township | 18 | 106 | 105 | -0.93% | 3 | 36.20 | Township |
| Lindaas township | 19 | 105 | 109 | -0.94% | 3 | 34.90 | Township |
| Roseville township | 20 | 95 | 90 | 2.15% | 3 | 35.54 | Township |
| Greenfield township | 21 | 94 | 97 | -1.05% | 3 | 35.33 | Township |
| Caledonia | 22 | 86 | 48 | 7.5% | 166 | 0.52 | CDP |
| Morgan township | 23 | 80 | 81 | 0% | 2 | 35.94 | Township |
| Belmont township | 24 | 77 | 78 | 0% | 3 | 25.01 | Township |
| Kelso township | 25 | 76 | 77 | 0% | 2 | 35.06 | Township |
| Blanchard township | 26 | 75 | 76 | 0% | 2 | 36.01 | Township |
| Bohnsack township | 27 | 73 | 74 | 0% | 2 | 35.06 | Township |
| Bingham township | 28 | 70 | 71 | 0% | 2 | 30.04 | Township |
| Galesburg township | 29 | 63 | 64 | 0% | 2 | 34.86 | Township |
| Herberg township | 30 | 47 | 50 | -2.08% | 1 | 33.72 | Township |
| Norman township | 31 | 37 | 40 | -2.63% | 1 | 35.83 | Township |
| Elm River township | 32 | 30 | 30 | 0% | 1 | 29 | Township |
| Clifford | 33 | 29 | 29 | 0% | 206 | 0.14 | City |
Mayville is the largest city in Traill County, with a population of 1,777.
Clifford is the smallest city in Traill County.
There are 33 cities in Traill County, North Dakota.