3 cities
| City | Rank | 2026 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Oak Harbor | 1 | 23,930 | 24,628 | -0.48% | 2,480 | 10 | City |
| Coupeville | 2 | 1,928 | 1,949 | -0.16% | 1,518 | 1 | Town |
| Langley | 3 | 1,134 | 1,149 | -0.18% | 1,125 | 1 | City |
Oak Harbor is the largest city in Island County, with a population of 23,930.
Langley is the smallest city in Island County, with a population of 1,134.
There are 3 cities in Island County, Washington.