33 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Mayville | 1 | 1,813 | 1,847 | -0.38% | 962 | 2 | City |
| Hillsboro | 2 | 1,663 | 1,650 | 0.12% | 1,496 | 1 | City |
| Hatton | 3 | 716 | 716 | 0% | 1,283 | 1 | City |
| Portland | 4 | 581 | 583 | -0.17% | 697 | 1 | City |
| Buxton | 5 | 354 | 348 | 0.28% | 1,060 | 0 | City |
| Viking | 6 | 181 | 168 | 1.69% | 5 | 35 | Township |
| Ervin | 7 | 174 | 168 | 0.58% | 5 | 36 | Township |
| Garfield | 8 | 172 | 173 | 0.58% | 5 | 35 | Township |
| Norway | 9 | 159 | 162 | -0.63% | 4 | 36 | Township |
| Bloomfield | 10 | 136 | 137 | 0% | 4 | 36 | Township |
| Wold | 11 | 126 | 123 | 0.8% | 4 | 36 | Township |
| Bohnsack | 12 | 114 | 113 | 0.88% | 3 | 35 | Township |
| Galesburg | 13 | 112 | 115 | -0.88% | 679 | 0 | City |
| Mayville | 14 | 112 | 111 | 0.9% | 3 | 35 | Township |
| Caledonia | 15 | 110 | 115 | -1.79% | 4 | 30 | Township |
| Eldorado | 16 | 110 | 110 | -1.79% | 3 | 36 | Township |
| Buxton | 17 | 109 | 108 | 0.93% | 3 | 35 | Township |
| Hillsboro | 18 | 107 | 106 | 0.94% | 3 | 35 | Township |
| Stavanger | 19 | 107 | 103 | 0% | 3 | 36 | Township |
| Lindaas | 20 | 105 | 104 | 0.96% | 3 | 35 | Township |
| Roseville | 21 | 92 | 89 | 1.1% | 3 | 36 | Township |
| Morgan | 22 | 89 | 80 | 5.95% | 2 | 36 | Township |
| Caledonia | 23 | 86 | 48 | 7.5% | 166 | 1 | CDP |
| Kelso | 24 | 80 | 79 | 1.27% | 2 | 35 | Township |
| Belmont | 25 | 78 | 77 | 1.3% | 3 | 25 | Township |
| Blanchard | 26 | 75 | 74 | 1.35% | 2 | 36 | Township |
| Bingham | 27 | 71 | 70 | 1.43% | 2 | 30 | Township |
| Galesburg | 28 | 63 | 62 | 1.61% | 2 | 35 | Township |
| Herberg | 29 | 55 | 55 | 0% | 2 | 34 | Township |
| Greenfield | 30 | 54 | 54 | 0% | 2 | 35 | Township |
| Norman | 31 | 43 | 43 | 0% | 1 | 36 | Township |
| Clifford | 32 | 31 | 31 | 0% | 220 | 0 | City |
| Elm River | 33 | 30 | 30 | 0% | 1 | 29 | Township |
Mayville is the largest city in Traill County, with a population of 1,813.
Elm River is the smallest city in Traill County, with a population of 30.
There are 33 cities in Traill County, North Dakota.