8 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Trumann | 1 | 7,397 | 7,481 | -0.19% | 1,261 | 6 | City |
| Harrisburg | 2 | 2,189 | 2,221 | -0.23% | 902 | 2 | City |
| Marked Tree | 3 | 2,148 | 2,277 | -0.97% | 372 | 6 | City |
| Lepanto | 4 | 1,591 | 1,731 | -1.43% | 1,017 | 2 | City |
| Tyronza | 5 | 654 | 717 | -1.51% | 421 | 2 | City |
| Weiner | 6 | 598 | 645 | -1.32% | 438 | 1 | City |
| Fisher | 7 | 166 | 178 | -1.19% | 557 | 0 | City |
| Waldenburg | 8 | 48 | 53 | -2.04% | 353 | 0 | Town |
Trumann is the largest city in Poinsett County, with a population of 7,397.
Waldenburg is the smallest city in Poinsett County, with a population of 48.
There are 8 cities in Poinsett County, Arkansas.