| Zip Code | City | Population ↓ |
|---|---|---|
| 15601 | Greensburg | 55,917 |
| 15642 | Irwin | 46,855 |
| 15068 | New Kensington | 36,199 |
| 15650 | Latrobe | 27,106 |
| 15644 | Jeannette | 18,665 |
| 15666 | Mount Pleasant | 15,592 |
| 15012 | Belle Vernon | 15,301 |
| 15668 | Murrysville | 14,179 |
| 15613 | Apollo | 12,541 |
| 15656 | Leechburg | 9,908 |
| 15632 | Export | 9,322 |
| 15658 | Ligonier | 8,364 |
| 15683 | Scottdale | 8,074 |
| 15085 | Trafford | 7,966 |
| 15062 | Monessen | 6,876 |
| 15089 | West Newton | 6,294 |
| 15627 | Derry | 6,032 |
| 15626 | Delmont | 4,967 |
| 15636 | Harrison City | 3,904 |
| 15610 | Acme | 3,827 |
| 15672 | New Stanton | 3,410 |
| 15944 | New Florence | 3,149 |
| 15670 | New Alexandria | 3,028 |
| 15697 | Youngwood | 2,933 |
| 15679 | Ruffs Dale | 2,501 |
| 15479 | Smithton | 2,071 |
| 15639 | Hunker | 1,924 |
| 15637 | Herminie | 1,678 |
| 15923 | Bolivar | 1,554 |
| 15675 | Penn | 1,472 |
| 15665 | Manor | 1,342 |
| 15687 | Stahlstown | 1,181 |
| 15661 | Loyalhanna | 1,006 |
| 15083 | Sutersville | 987 |
| 15662 | Luxor | 951 |
| 15688 | Tarrs | 814 |
| 15623 | Claridge | 737 |
| 15676 | Pleasant Unity | 717 |
| 15629 | East Vandergrift | 701 |
| 15671 | New Derry | 674 |
| 15698 | Yukon | 672 |
| 15692 | Westmoreland City | 671 |
| 15620 | Bradenville | 632 |
| 15633 | Forbes Road | 613 |
| 15678 | Rillton | 528 |
| 15779 | Torrance | 527 |
| 15640 | Hutchinson | 505 |
| 15641 | Hyde Park | 501 |
| 15684 | Slickville | 460 |
| 15663 | Madison | 451 |
| 15691 | Wendel | 427 |
| 15616 | Armbrust | 427 |
| 15624 | Crabtree | 402 |
| 15628 | Donegal | 389 |
| 15677 | Rector | 376 |
| 15612 | Alverton | 375 |
| 15634 | Grapeville | 343 |
| 15695 | Wyano | 313 |
| 15693 | Whitney | 292 |
| 15619 | Bovard | 291 |
| 15674 | Norvelt | 271 |
| 15655 | Laughlintown | 269 |
| 15617 | Arona | 255 |
| 15696 | Youngstown | 251 |
| 15615 | Ardara | 223 |
| 15680 | Salina | 222 |
| 15448 | Jacobs Creek | 204 |
| 15660 | Lowber | 196 |
| 15611 | Adamsburg | 161 |
| 15646 | Jones Mills | 160 |
| 15625 | Darragh | 97 |
| 15087 | Webster | 82 |
| 15635 | Hannastown | 79 |
| 15689 | United | 74 |
| 15638 | Hostetter | 62 |
| 15072 | Pricedale | 44 |
| 15647 | Larimer | 37 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 77 ZCTAs in Westmoreland County, Pennsylvania (US Census).