38 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Eureka | 1 | 25,147 | 26,471 | -1.04% | 2,629 | 10 | City |
| Arcata | 2 | 18,725 | 18,837 | -0.12% | 1,989 | 9 | City |
| McKinleyville | 3 | 17,347 | 16,645 | 0.84% | 831 | 21 | CDP |
| Fortuna | 4 | 12,018 | 12,495 | -0.79% | 2,288 | 5 | City |
| Myrtletown | 5 | 5,014 | 5,143 | 0.46% | 2,391 | 2 | CDP |
| Pine Hills | 6 | 3,602 | 3,547 | 0.87% | 356 | 10 | CDP |
| Cutten | 7 | 3,359 | 3,315 | 0.51% | 2,616 | 1 | CDP |
| Humboldt Hill | 8 | 3,238 | 3,435 | -0.37% | 779 | 4 | CDP |
| Rio Dell | 9 | 3,226 | 3,388 | -1.01% | 1,299 | 2 | City |
| Hoopa | 10 | 3,111 | 3,348 | 7.13% | 152 | 20 | CDP |
| Bayview | 11 | 2,771 | 2,787 | 0.62% | 3,760 | 1 | CDP |
| Garberville | 12 | 2,041 | 1,361 | 3.87% | 762 | 3 | CDP |
| Ferndale | 13 | 1,351 | 1,399 | -0.73% | 1,120 | 1 | City |
| Westhaven-Moonstone | 14 | 1,321 | 1,302 | 0.53% | 163 | 8 | CDP |
| Willow Creek | 15 | 1,286 | 1,241 | -2.13% | 42 | 30 | CDP |
| Redway | 16 | 1,265 | 1,315 | 0.24% | 1,011 | 1 | CDP |
| Blue Lake | 17 | 1,146 | 1,211 | -1.12% | 1,854 | 1 | City |
| Hydesville | 18 | 1,016 | 1,051 | -1.36% | 135 | 8 | CDP |
| Fieldbrook | 19 | 756 | 793 | -0.92% | 72 | 10 | CDP |
| Fields Landing | 20 | 717 | 577 | 4.22% | 2,588 | 0 | CDP |
| Indianola | 21 | 690 | 660 | -1.29% | 489 | 1 | CDP |
| Miranda | 22 | 690 | 498 | 1.62% | 462 | 1 | CDP |
| Manila | 23 | 633 | 762 | -1.56% | 908 | 1 | CDP |
| Loleta | 24 | 469 | 599 | -4.29% | 221 | 2 | CDP |
| Shelter Cove | 25 | 452 | 863 | -3.42% | 78 | 6 | CDP |
| Fairhaven | 26 | 426 | 254 | 7.04% | 655 | 1 | CDP |
| Scotia | 27 | 425 | 490 | -6.18% | 570 | 1 | CDP |
| Trinidad | 28 | 317 | 337 | -1.25% | 650 | 0 | City |
| Orick | 29 | 296 | 346 | -1.33% | 62 | 5 | CDP |
| Myers Flat | 30 | 223 | 126 | 2.29% | 516 | 0 | CDP |
| Samoa | 31 | 214 | 211 | -1.38% | 256 | 1 | CDP |
| Ruth | 32 | 140 | 213 | -2.78% | 4 | 39 | CDP |
| Big Lagoon | 33 | 130 | 92 | 7.44% | 214 | 1 | CDP |
| Benbow | 34 | 111 | 152 | -11.2% | 23 | 5 | CDP |
| Weitchpec | 35 | 99 | 58 | 7.61% | 26 | 4 | CDP |
| Alderpoint | 36 | 67 | 26 | -10.67% | 28 | 2 | CDP |
| Kep'el | 37 | 24 | 26 | 9.09% | 7 | 4 | CDP |
| Wautec | 38 | 21 | 15 | 5% | 9 | 2 | CDP |
Eureka is the largest city in Humboldt County, with a population of 25,147.
Wautec is the smallest city in Humboldt County, with a population of 21.
There are 38 cities in Humboldt County, California.