Note: As defined by the US Census Bureau, a city's official boundaries often extend miles beyond the city itself and may even cross county lines. As such, several thousand US cities officially exist in two or more counties (and therefore appear on multiple counties' lists of cities.)
City | Rank | 2024 Pop. | 2020 Pop. | Change | Density (/mi²) | Area (mi²) | Type |
|---|---|---|---|---|---|---|---|
| Robinson township | 1 | 15,591 | 15,509 | 0.53% | 1,025 | 15.2 | Township |
| Indiana | 2 | 14,376 | 14,026 | 0.61% | 8,173 | 1.8 | Borough |
| Indiana township | 3 | 7,214 | 7,245 | -0.83% | 411 | 17.6 | Township |
| Center township | 4 | 4,376 | 4,385 | 0.14% | 109 | 40.2 | Township |
| Armagh township | 5 | 4,081 | 4,019 | 0.89% | 44 | 92.8 | Township |
| Burrell township | 6 | 3,453 | 3,477 | -0.12% | 145 | 23.8 | Township |
| Green township | 7 | 3,395 | 3,411 | 0.03% | 65 | 52.5 | Township |
| Blairsville | 8 | 3,199 | 3,215 | -0.13% | 2,262 | 1.4 | Borough |
| Rayne township | 9 | 2,764 | 2,784 | -0.04% | 59 | 47.1 | Township |
| Armstrong township | 10 | 2,755 | 2,760 | 0.11% | 73 | 37.6 | Township |
| Cherryhill township | 11 | 2,431 | 2,443 | 0.08% | 50 | 48.6 | Township |
| East Wheatfield township | 12 | 2,130 | 2,136 | 0.05% | 78 | 27.2 | Township |
| West Wheatfield township | 13 | 2,126 | 2,139 | 0.09% | 67 | 31.6 | Township |
| Conemaugh township | 14 | 2,052 | 2,056 | 0.19% | 61 | 33.7 | Township |
| Pine township | 15 | 1,852 | 1,857 | 0.16% | 60 | 31.0 | Township |
| South Mahoning township | 16 | 1,815 | 1,821 | 0.06% | 64 | 28.6 | Township |
| Homer City | 17 | 1,713 | 1,724 | -0.18% | 3,103 | 0.6 | Borough |
| Young township | 18 | 1,682 | 1,691 | 0% | 48 | 34.8 | Township |
| Robinson township | 19 | 1,678 | 1,706 | -0.36% | 79 | 21.2 | Township |
| Brush Valley township | 20 | 1,670 | 1,673 | 0.12% | 40 | 41.3 | Township |
| Canoe township | 21 | 1,435 | 1,428 | 0.49% | 53 | 27.0 | Township |
| North Mahoning township | 22 | 1,329 | 1,332 | 0.07% | 47 | 28.2 | Township |
| West Mahoning township | 23 | 1,318 | 1,322 | 0.15% | 46 | 28.9 | Township |
| Clymer | 24 | 1,312 | 1,320 | -0.15% | 2,306 | 0.6 | Borough |
| Buffington township | 25 | 1,224 | 1,227 | 0.08% | 40 | 30.6 | Township |
| Black Lick township | 26 | 1,116 | 1,120 | 0% | 40 | 27.7 | Township |
| Saltsburg | 27 | 764 | 768 | -0.13% | 3,691 | 0.2 | Borough |
| Ernest | 28 | 415 | 415 | 0% | 1,804 | 0.2 | Borough |
| Marion Center | 29 | 407 | 409 | -0.24% | 548 | 0.7 | Borough |
| Creekside | 30 | 281 | 284 | -0.36% | 1,271 | 0.2 | Borough |
| Cherry Tree | 31 | 268 | 271 | -0.37% | 534 | 0.5 | Borough |
| Glen Campbell | 32 | 249 | 252 | -0.4% | 267 | 0.9 | Borough |
| Plumville | 33 | 248 | 251 | -0.4% | 500 | 0.5 | Borough |
| Shelocta | 34 | 100 | 102 | -0.99% | 962 | 0.1 | Borough |
| Armagh | 35 | 99 | 101 | -1% | 1,737 | 0.1 | Borough |
| Smicksburg | 36 | 56 | 56 | 0% | 384 | 0.1 | Borough |
Note: City markers shown outside the county boundary mean that a part of the city extends into this county, but is primarily located in an adjacent county.
Robinson township is the largest city in Indiana County.
Smicksburg is the smallest city in Indiana County.
There are 36 cities in Indiana County, Pennsylvania.