11 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 61856 | Monticello | 8,226 |
| 61813 | Bement | 2,043 |
| 61818 | Cerro Gordo | 1,560 |
| 61913 | Atwood | 1,300 |
| 61854 | Mansfield | 1,299 |
| 61884 | White Heath | 973 |
| 61929 | Hammond | 672 |
| 61839 | De Land | 558 |
| 61830 | Cisco | 510 |
| 61936 | La Place | 170 |
| 61855 | Milmine | 24 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 11 ZCTAs in Piatt County, Illinois (US Census).