Identifiers: city · CDP · borough
| Rank | Community | Population |
|---|---|---|
| 1 | Allentown (city), PA | 125,845 |
| 2 | Bethlehem (city), PA | 75,781 |
| 3 | Fullerton (CDP), PA | 16,588 |
| 4 | Emmaus (borough), PA | 11,652 |
| 5 | Northampton (borough), PA | 10,395 |
| 6 | Quakertown (borough), PA | 9,359 |
| 7 | Middletown (CDP), PA | 7,529 |
| 8 | Breinigsville (CDP), PA | 7,495 |
| 9 | Ancient Oaks (CDP), PA | 6,995 |
| 10 | Catasauqua (borough), PA | 6,518 |
| 11 | Hellertown (borough), PA | 6,132 |
| 12 | Wescosville (CDP), PA | 6,039 |
| 13 | Palmerton (borough), PA | 5,593 |
| 14 | Lehighton (borough), PA | 5,248 |
| 15 | Dorneyville (CDP), PA | 4,850 |
| 16 | Fountain Hill (borough), PA | 4,832 |
| 17 | Slatington (borough), PA | 4,283 |
| 18 | Kutztown (borough), PA | 4,162 |
| 19 | Coplay (borough), PA | 3,348 |
| 20 | Hokendauqua (CDP), PA | 3,340 |