34 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Frederick | 1 | 90,748 | 78,360 | 2.81% | 3,787 | 23.96 | City |
| Ballenger Creek | 2 | 25,838 | 21,484 | 1.99% | 2,393 | 10.80 | CDP |
| Green Valley | 3 | 16,225 | 12,391 | 7.14% | 949 | 17.09 | CDP |
| Urbana | 4 | 14,423 | 12,362 | 2.49% | 1,856 | 7.77 | CDP |
| Linganore | 5 | 12,702 | 9,988 | 2.24% | 1,535 | 8.28 | CDP |
| Mount Airy | 6 | 10,040 | 9,662 | 0.76% | 2,435 | 4.12 | Town |
| Brunswick | 7 | 8,651 | 7,796 | 2.02% | 2,642 | 3.27 | City |
| Thurmont | 8 | 6,969 | 6,246 | 2.13% | 2,243 | 3.11 | Town |
| Walkersville | 9 | 6,897 | 6,179 | 2.13% | 1,448 | 4.76 | Town |
| Spring Ridge | 10 | 5,665 | 5,612 | -0.16% | 2,104 | 2.69 | CDP |
| Middletown | 11 | 5,536 | 4,963 | 2.12% | 2,614 | 2.12 | Town |
| Monrovia | 12 | 3,621 | 1,556 | 6.28% | 1,613 | 2.25 | CDP |
| Emmitsburg | 13 | 3,080 | 2,777 | 2.02% | 1,905 | 1.62 | Town |
| Braddock Heights | 14 | 2,919 | 3,093 | 0.73% | 547 | 5.34 | CDP |
| Jefferson | 15 | 2,900 | 2,577 | 1.86% | 1,041 | 2.79 | CDP |
| Bartonsville | 16 | 2,604 | 1,786 | 3.05% | 1,219 | 2.14 | CDP |
| Point Rocks | 17 | 2,584 | 2,067 | 2.99% | 2,307 | 1.12 | CDP |
| Adamstown | 18 | 2,400 | 2,130 | 0.08% | 2,256 | 1.06 | CDP |
| Myersville | 19 | 2,027 | 1,816 | 2.12% | 1,746 | 1.16 | Town |
| New Market | 20 | 1,711 | 1,536 | 2.09% | 967 | 1.77 | Town |
| Libertytown | 21 | 1,356 | 831 | 2.03% | 563 | 2.41 | CDP |
| Buckeystown | 22 | 1,289 | 1,289 | 1.42% | 1,412 | 0.91 | CDP |
| Woodsboro | 23 | 1,224 | 1,099 | 2.08% | 1,731 | 0.71 | Town |
| Highfield-Cascade | 24 | 1,011 | 912 | -0.69% | 584 | 1.73 | CDP |
| Sabillasville | 25 | 418 | 390 | 0.97% | 250 | 1.67 | CDP |
| Lewistown | 26 | 409 | 410 | 7.07% | 639 | 0.64 | CDP |
| Garretts Mill | 27 | 334 | 350 | 2.14% | 585 | 0.57 | CDP |
| Rosemont | 28 | 303 | 275 | 2.02% | 545 | 0.56 | Village |
| Graceham | 29 | 254 | 304 | 7.17% | 530 | 0.48 | CDP |
| Edgemont | 30 | 247 | 277 | 0.41% | 466 | 0.53 | CDP |
| Sandy Hook | 31 | 207 | 193 | 0.48% | 958 | 0.22 | CDP |
| Yarrowsburg | 32 | 182 | 274 | 2.25% | 802 | 0.23 | CDP |
| Burkittsville | 33 | 154 | 141 | 1.99% | 339 | 0.45 | Town |
| Greensburg | 34 | 89 | 126 | -9.18% | 220 | 0.40 | CDP |
Frederick is the largest city in Frederick County, with a population of 90,748.
Greensburg is the smallest city in Frederick County.
There are 34 cities in Frederick County, Maryland.