20 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Highlands Ranch | 1 | 102,714 | 107,017 | 0.39% | 4,232 | 24 | CDP |
| Castle Rock | 2 | 85,544 | 73,888 | 2.8% | 2,462 | 35 | Town |
| Parker | 3 | 67,128 | 58,853 | 2.53% | 2,991 | 22 | Town |
| Castle Pines | 4 | 16,149 | 11,213 | 6.51% | 1,683 | 10 | City |
| Black Forest | 5 | 14,767 | 13,103 | 0.75% | 147 | 101 | CDP |
| The Pinery | 6 | 10,538 | 10,033 | 0.01% | 1,015 | 10 | CDP |
| Stonegate | 7 | 9,972 | 9,860 | 0.68% | 5,446 | 2 | CDP |
| Roxborough Park | 8 | 9,046 | 9,004 | -0.04% | 980 | 9 | CDP |
| Castle Pines Village | 9 | 5,577 | 4,558 | 7.13% | 1,253 | 4 | CDP |
| Sierra Ridge | 10 | 3,666 | 1,742 | 7.13% | 7,231 | 1 | CDP |
| Stepping Stone | 11 | 3,458 | 1,798 | 7.16% | 4,705 | 1 | CDP |
| Meridian Village | 12 | 3,124 | 2,840 | 7.13% | 6,125 | 1 | CDP |
| Acres Green | 13 | 2,532 | 2,888 | -1.25% | 4,213 | 1 | CDP |
| Sterling Ranch | 14 | 2,375 | 521 | 7.13% | 430 | 6 | CDP |
| Perry Park | 15 | 1,728 | 1,821 | 0.29% | 202 | 9 | CDP |
| Grand View Estates | 16 | 853 | 760 | 2.65% | 855 | 1 | CDP |
| Franktown | 17 | 340 | 214 | -1.16% | 115 | 3 | CDP |
| Westcreek | 18 | 319 | 273 | 4.25% | 262 | 1 | CDP |
| Louviers | 19 | 265 | 381 | -0.38% | 168 | 2 | CDP |
| Larkspur | 20 | 226 | 208 | 1.35% | 142 | 2 | Town |
Highlands Ranch is the largest city in Douglas County, with a population of 102,714.
Larkspur is the smallest city in Douglas County, with a population of 226.
There are 20 cities in Douglas County, Colorado.