5 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Marshall | 1 | 24,492 | 23,346 | 0.94% | 823 | 30 | City |
| Hallsville | 2 | 5,045 | 4,298 | 3.04% | 1,326 | 4 | City |
| Waskom | 3 | 1,950 | 1,907 | 0.41% | 728 | 3 | City |
| Scottsville | 4 | 340 | 334 | 0.29% | 258 | 1 | City |
| Uncertain | 5 | 85 | 85 | 0% | 158 | 1 | City |
Marshall is the largest city in Harrison County, with a population of 24,492.
Uncertain is the smallest city in Harrison County, with a population of 85.
There are 5 cities in Harrison County, Texas.