31 zips
| Zip Code | City | Population ↓ |
|---|---|---|
| 16001 | Butler | 39,733 |
| 16066 | Cranberry Township | 33,543 |
| 16046 | Mars | 19,577 |
| 16002 | Butler | 15,722 |
| 16057 | Slippery Rock | 15,264 |
| 16059 | Valencia | 9,770 |
| 16055 | Sarver | 8,856 |
| 16063 | Zelienople | 8,188 |
| 16033 | Evans City | 7,934 |
| 16025 | Chicora | 4,880 |
| 16037 | Harmony | 4,840 |
| 16056 | Saxonburg | 4,429 |
| 16023 | Cabot | 4,130 |
| 16053 | Renfrew | 3,284 |
| 16038 | Harrisville | 3,213 |
| 16051 | Portersville | 3,118 |
| 16061 | West Sunbury | 2,578 |
| 16052 | Prospect | 2,246 |
| 16041 | Karns City | 1,865 |
| 16034 | Fenelton | 1,781 |
| 16020 | Boyers | 1,179 |
| 16045 | Lyndora | 1,109 |
| 16040 | Hilliards | 1,013 |
| 16050 | Petrolia | 978 |
| 16029 | East Butler | 902 |
| 16027 | Connoquenessing | 441 |
| 16022 | Bruin | 296 |
| 16024 | Callery | 278 |
| 16030 | Eau Claire | 253 |
| 16048 | North Washington | 225 |
| 16035 | Forestville | 144 |
The data shown reflect ZCTAs from the US Census. As of 2024, there are 31 ZCTAs in Butler County, Pennsylvania (US Census).