23 cities
| City | Rank | 2025 Pop. ↓ | 2020 Pop. | Change | Density | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Fort Wayne | 1 | 273,736 | 264,380 | 0.69% | 2,474 | 110.63 | City |
| Wayne township | 2 | 111,096 | 107,639 | 0.64% | 2,637 | 42.12 | Township |
| St. Joseph township | 3 | 79,346 | 76,494 | 0.74% | 2,258 | 35.15 | Township |
| Aboite township | 4 | 43,799 | 42,167 | 0.76% | 1,318 | 33.22 | Township |
| Perry township | 5 | 39,119 | 37,663 | 0.76% | 1,102 | 35.50 | Township |
| Adams township | 6 | 35,489 | 34,171 | 0.76% | 1,071 | 33.12 | Township |
| New Haven | 7 | 16,218 | 15,608 | 0.76% | 1,363 | 11.90 | City |
| Cedar Creek township | 8 | 14,238 | 13,712 | 0.76% | 413 | 34.48 | Township |
| Huntertown | 9 | 11,481 | 11,068 | 0.73% | 1,639 | 7 | Town |
| Springfield township | 10 | 4,715 | 4,544 | 0.75% | 134 | 35.31 | Township |
| Eel River township | 11 | 4,360 | 4,203 | 0.74% | 119 | 36.51 | Township |
| Leo-Cedarville | 12 | 3,775 | 3,637 | 0.75% | 1,014 | 3.72 | Town |
| Pleasant township | 13 | 3,080 | 2,971 | 0.75% | 88 | 35.03 | Township |
| Lake township | 14 | 2,900 | 2,798 | 0.73% | 81 | 35.67 | Township |
| Maumee township | 15 | 2,745 | 2,638 | 0.84% | 104 | 26.37 | Township |
| Jefferson township | 16 | 2,123 | 2,054 | 0.62% | 58 | 36.53 | Township |
| Woodburn | 17 | 1,615 | 1,554 | 0.75% | 1,677 | 0.96 | City |
| Harlan | 18 | 1,608 | 1,715 | -0.12% | 462 | 3.48 | CDP |
| Monroeville | 19 | 1,350 | 1,299 | 0.75% | 1,722 | 0.78 | Town |
| Grabill | 20 | 1,164 | 1,113 | 0.87% | 1,788 | 0.65 | Town |
| Hoagland | 21 | 892 | 908 | 0.45% | 263 | 3.40 | CDP |
| Zanesville | 22 | 594 | 579 | 0.51% | 718 | 0.83 | Town |
| Jackson township | 23 | 527 | 505 | 0.96% | 21 | 25.50 | Township |
Fort Wayne is the largest city in Allen County, with a population of 273,736.
Jackson township is the smallest city in Allen County.
There are 23 cities in Allen County, Indiana.