8 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Shelton | 1 | 10,812 | 10,371 | 0.7% | 1,859 | 6 | City |
| Shelton | 2 | 10,812 | 10,436 | 0.7% | 1,859 | 6 | City |
| Belfair | 3 | 4,236 | 4,557 | 0.47% | 575 | 7 | CDP |
| Allyn | 4 | 2,321 | 2,504 | 1.04% | 1,453 | 2 | CDP |
| Grapeview | 5 | 1,172 | 703 | 1.3% | 319 | 4 | CDP |
| Skokomish | 6 | 651 | 635 | 0.46% | 98 | 7 | CDP |
| Union | 7 | 350 | 327 | -4.89% | 216 | 2 | CDP |
| Hoodsport | 8 | 108 | 139 | -14.29% | 102 | 1 | CDP |
Shelton is the largest city in Mason County, with a population of 10,812.
Hoodsport is the smallest city in Mason County, with a population of 108.
There are 8 cities in Mason County, Washington.