31 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 16001 | Butler | 39,234 |
| 16066 | Cranberry Township | 33,873 |
| 16046 | Mars | 19,757 |
| 16057 | Slippery Rock | 15,718 |
| 16002 | Butler | 15,587 |
| 16059 | Valencia | 10,062 |
| 16055 | Sarver | 8,993 |
| 16063 | Zelienople | 8,256 |
| 16033 | Evans City | 8,185 |
| 16037 | Harmony | 5,291 |
| 16025 | Chicora | 4,793 |
| 16056 | Saxonburg | 4,232 |
| 16023 | Cabot | 4,082 |
| 16053 | Renfrew | 3,429 |
| 16038 | Harrisville | 3,292 |
| 16051 | Portersville | 3,119 |
| 16061 | West Sunbury | 2,564 |
| 16052 | Prospect | 2,215 |
| 16034 | Fenelton | 1,752 |
| 16041 | Karns City | 1,747 |
| 16020 | Boyers | 1,169 |
| 16045 | Lyndora | 1,136 |
| 16050 | Petrolia | 1,097 |
| 16040 | Hilliards | 1,013 |
| 16029 | East Butler | 916 |
| 16027 | Connoquenessing | 423 |
| 16030 | Eau Claire | 272 |
| 16035 | Forestville | 252 |
| 16048 | North Washington | 225 |
| 16022 | Bruin | 219 |
| 16024 | Callery | 210 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 31 ZCTAs in Butler County, Pennsylvania (US Census).