31 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Annual Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Hampden | 1 | 35,928 | 33,025 | 1.28% | 2,081 | 17 | Township |
| Upper Allen | 2 | 24,889 | 23,265 | 1.7% | 1,879 | 13 | Township |
| Carlisle | 3 | 23,109 | 20,149 | 2.63% | 4,177 | 6 | Borough |
| East Pennsboro | 4 | 21,738 | 20,910 | 1.15% | 2,062 | 11 | Township |
| Lower Allen | 5 | 21,307 | 20,132 | 2.08% | 2,117 | 10 | Township |
| South Middleton | 6 | 18,257 | 16,172 | 3.96% | 374 | 49 | Township |
| North Middleton | 7 | 13,055 | 12,100 | 1.65% | 563 | 23 | Township |
| Mechanicsburg | 8 | 10,266 | 9,361 | 1.79% | 4,258 | 2 | Borough |
| Camp Hill | 9 | 8,259 | 8,117 | 0.34% | 3,887 | 2 | Borough |
| Middlesex | 10 | 7,719 | 7,033 | 3.49% | 300 | 26 | Township |
| New Cumberland | 11 | 7,651 | 7,520 | 0.34% | 4,568 | 2 | Borough |
| Monroe | 12 | 6,865 | 6,256 | 1.67% | 264 | 26 | Township |
| Plainfield | 13 | 6,277 | 6,244 | 0.32% | 254 | 25 | Township |
| West Pennsboro | 14 | 5,746 | 5,593 | 0.68% | 190 | 30 | Township |
| Shippensburg | 15 | 5,676 | 5,484 | 0.67% | 2,799 | 2 | Borough |
| Dickinson | 16 | 5,516 | 5,303 | 0.84% | 120 | 46 | Township |
| Lemoyne | 17 | 4,862 | 4,672 | 0.79% | 3,016 | 2 | Borough |
| Shippensburg | 18 | 4,339 | 4,286 | 0.28% | 1,749 | 2 | Township |
| Wormleysburg | 19 | 3,106 | 3,055 | 0.32% | 3,997 | 1 | Borough |
| North Newton | 20 | 2,634 | 2,557 | 0.8% | 116 | 23 | Township |
| Upper Frankford | 21 | 2,298 | 2,133 | 1.59% | 118 | 19 | Township |
| Mount Holly Springs | 22 | 2,030 | 1,998 | 0.3% | 1,494 | 1 | Borough |
| Lower Frankford | 23 | 1,878 | 1,755 | 1.95% | 128 | 15 | Township |
| Lower Mifflin | 24 | 1,798 | 1,756 | 0.45% | 76 | 24 | Township |
| Shiremanstown | 25 | 1,674 | 1,648 | 0.3% | 5,471 | 0 | Borough |
| Newville | 26 | 1,417 | 1,389 | 0.35% | 3,382 | 0 | Borough |
| South Newton | 27 | 1,400 | 1,371 | 0.57% | 124 | 11 | Township |
| Upper Mifflin | 28 | 1,376 | 1,317 | 0.51% | 63 | 22 | Township |
| Newburg | 29 | 362 | 350 | 0.56% | 1,957 | 0 | Borough |
| Cooke | 30 | 212 | 204 | 1.44% | 11 | 20 | Township |
| Newburg | 31 | 81 | 83 | -1.22% | 44 | 2 | Borough |
Hampden is the largest city in Cumberland County, with a population of 35,928.
Newburg is the smallest city in Cumberland County, with a population of 81.
There are 31 cities in Cumberland County, Pennsylvania.