26 ZIP Codes
| Zip Code | City | Population ↓ |
|---|---|---|
| 61350 | Ottawa | 23,713 |
| 61364 | Streator | 17,963 |
| 61301 | La Salle | 10,398 |
| 61354 | Peru | 10,290 |
| 61342 | Mendota | 8,543 |
| 61341 | Marseilles | 7,692 |
| 60551 | Sheridan | 5,058 |
| 61348 | Oglesby | 4,375 |
| 61360 | Seneca | 3,610 |
| 60518 | Earlville | 3,289 |
| 61373 | Utica | 2,123 |
| 60531 | Leland | 1,885 |
| 61377 | Wenona | 1,441 |
| 61370 | Tonica | 1,215 |
| 61325 | Grand Ridge | 949 |
| 60549 | Serena | 784 |
| 61334 | Lostant | 738 |
| 60537 | Millington | 726 |
| 61358 | Rutland | 407 |
| 60470 | Ransom | 358 |
| 61372 | Troy Grove | 300 |
| 61316 | Cedar Point | 256 |
| 61321 | Dana | 224 |
| 61332 | Leonore | 104 |
| 61371 | Triumph | 83 |
| 60557 | Wedron | 0 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 26 ZCTAs in LaSalle County, Illinois (US Census).