Identifiers: borough · CDP · city
| Rank | Community | Population |
|---|---|---|
| 1 | Franklin Park (borough), PA | 15,479 |
| 2 | Carnot-Moon (CDP), PA | 13,151 |
| 3 | Aliquippa (city), PA | 9,238 |
| 4 | Economy (borough), PA | 9,098 |
| 5 | Beaver Falls (city), PA | 9,005 |
| 6 | Bellevue (borough), PA | 8,311 |
| 7 | Ellwood City (borough), PA | 7,642 |
| 8 | Ambridge (borough), PA | 6,972 |
| 9 | New Brighton (borough), PA | 5,729 |
| 10 | Monaca (borough), PA | 5,625 |
| 11 | Coraopolis (borough), PA | 5,559 |
| 12 | Avalon (borough), PA | 4,762 |
| 13 | Beaver (borough), PA | 4,438 |
| 14 | Zelienople (borough), PA | 3,912 |
| 15 | Sewickley (borough), PA | 3,907 |
| 16 | Baden (borough), PA | 3,904 |
| 17 | Rochester (borough), PA | 3,472 |
| 18 | Ohioville (borough), PA | 3,349 |
| 19 | Seven Fields (borough), PA | 2,919 |
| 20 | Imperial (CDP), PA | 2,722 |