5 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Astoria | 1 | 9,764 | 10,190 | -0.72% | 1,598 | 6 | City |
| Seaside | 2 | 7,077 | 7,176 | -0.23% | 1,748 | 4 | City |
| Warrenton | 3 | 6,343 | 6,286 | 0.16% | 501 | 13 | City |
| Gearhart | 4 | 1,901 | 1,813 | 0.8% | 1,017 | 2 | City |
| Cannon Beach | 5 | 1,498 | 1,504 | -0.07% | 958 | 2 | City |
Astoria is the largest city in Clatsop County, with a population of 9,764.
Cannon Beach is the smallest city in Clatsop County, with a population of 1,498.
There are 5 cities in Clatsop County, Oregon.