47 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Lebanon | 1 | 26,100 | 26,794 | -0.53% | 6,263 | 4.17 | City |
| Richland township | 2 | 14,406 | 13,826 | 0.8% | 698 | 20.65 | Township |
| North Lebanon township | 3 | 12,186 | 12,049 | 0.33% | 728 | 16.75 | Township |
| Richland township | 4 | 11,869 | 12,232 | -0.51% | 574 | 20.68 | Township |
| Richland township | 5 | 11,569 | 11,929 | -0.71% | 791 | 14.63 | Township |
| South Lebanon township | 6 | 10,672 | 10,423 | 0.56% | 492 | 21.68 | Township |
| North Cornwall township | 7 | 10,017 | 8,509 | 3% | 1,055 | 9.50 | Township |
| North Londonderry township | 8 | 9,007 | 8,917 | 0.3% | 839 | 10.74 | Township |
| South Londonderry township | 9 | 8,765 | 8,786 | -0.17% | 360 | 24.35 | Township |
| Palmyra | 10 | 7,622 | 7,821 | -0.52% | 3,964 | 1.92 | Borough |
| Campbelltown | 11 | 6,227 | 5,632 | 2.87% | 1,935 | 3.22 | CDP |
| Swatara township | 12 | 4,994 | 5,059 | -0.28% | 232 | 21.57 | Township |
| Annville township | 13 | 4,974 | 4,755 | 0.24% | 3,067 | 1.62 | Township |
| Annville | 14 | 4,845 | 5,001 | 0.12% | 2,987 | 1.62 | CDP |
| Cornwall | 15 | 4,630 | 4,609 | 0.09% | 477 | 9.70 | Borough |
| Millcreek township | 16 | 4,408 | 4,366 | 0.27% | 216 | 20.43 | Township |
| Heidelberg township | 17 | 4,020 | 4,100 | -0.25% | 166 | 24.24 | Township |
| South Annville township | 18 | 3,467 | 3,438 | 0.26% | 178 | 19.47 | Township |
| Pleasant Hill | 19 | 3,418 | 2,962 | 1.54% | 4,695 | 0.73 | CDP |
| Palmyra township | 20 | 3,355 | 3,205 | 0.54% | 98 | 34.14 | Township |
| Myerstown | 21 | 3,117 | 3,097 | 0.13% | 3,641 | 0.86 | Borough |
| Union township | 22 | 2,880 | 2,932 | -0.28% | 97 | 29.64 | Township |
| Newmanstown | 23 | 2,876 | 2,798 | 0.95% | 1,320 | 2.18 | CDP |
| East Hanover township | 24 | 2,686 | 2,657 | 0.3% | 83 | 32.46 | Township |
| Sand Hill | 25 | 2,534 | 2,653 | 0.12% | 2,516 | 1.01 | CDP |
| North Annville township | 26 | 2,288 | 2,277 | 0.18% | 133 | 17.26 | Township |
| Lebanon South | 27 | 2,036 | 2,083 | -0.78% | 2,627 | 0.78 | CDP |
| Cleona | 28 | 2,024 | 2,013 | 0.1% | 2,427 | 0.83 | Borough |
| West Cornwall township | 29 | 2,006 | 1,995 | 0.2% | 232 | 8.64 | Township |
| Fredericksburg | 30 | 1,736 | 1,784 | 1.52% | 905 | 1.92 | CDP |
| Jonestown | 31 | 1,651 | 1,636 | 0.18% | 2,604 | 0.63 | Borough |
| Richland | 32 | 1,506 | 1,496 | 0.13% | 1,087 | 1.39 | Borough |
| Avon | 33 | 1,334 | 1,798 | -1.69% | 969 | 1.38 | CDP |
| Palmyra township | 34 | 1,257 | 1,242 | 0.24% | 79 | 15.90 | Township |
| Fredericksburg | 35 | 1,111 | 964 | 2.4% | 633 | 1.75 | CDP |
| Hebron | 36 | 1,024 | 1,079 | -1.73% | 6,400 | 0.16 | CDP |
| Richland township | 37 | 758 | 774 | -0.39% | 34 | 22.22 | Township |
| Schaefferstown | 38 | 699 | 907 | -2.24% | 259 | 2.69 | CDP |
| Quentin | 39 | 697 | 737 | 1.01% | 638 | 1.09 | CDP |
| Lebanon township | 40 | 690 | 678 | 0.15% | 19 | 37.25 | Township |
| Timber Hills | 41 | 512 | 502 | 1.99% | 766 | 0.67 | CDP |
| Richland township | 42 | 470 | 469 | -0.63% | 31 | 15.07 | Township |
| Mount Gretna Heights | 43 | 216 | 286 | -3.14% | 1,143 | 0.19 | CDP |
| Mount Gretna | 44 | 188 | 187 | 0% | 1,306 | 0.14 | Borough |
| Fredericksburg | 45 | 181 | 186 | 7.1% | 529 | 0.34 | CDP |
| Jonestown | 46 | 80 | 91 | 6.67% | 218 | 0.37 | CDP |
| Cold Spring township | 47 | 64 | 59 | 3.23% | 3 | 24.81 | Township |
Lebanon is the largest city in Lebanon County, with a population of 26,100.
Cold Spring township is the smallest city in Lebanon County.
There are 47 cities in Lebanon County, Pennsylvania.