Zip Code | City | Population |
|---|---|---|
| 60440 | Bolingbrook | 51,412 |
| 60435 | Joliet | 48,574 |
| 60586 | Plainfield | 48,029 |
| 60564 | Naperville | 46,832 |
| 60446 | Romeoville | 41,253 |
| 60451 | New Lenox | 37,488 |
| 60441 | Lockport | 37,046 |
| 60423 | Frankfort | 32,596 |
| 60544 | Plainfield | 28,073 |
| 60431 | Joliet | 27,357 |
| 60585 | Plainfield | 24,754 |
| 60448 | Mokena | 24,626 |
| 60491 | Homer Glen | 22,779 |
| 60490 | Bolingbrook | 22,343 |
| 60432 | Joliet | 20,483 |
| 60404 | Shorewood | 19,668 |
| 60436 | Joliet | 18,452 |
| 60403 | Crest Hill | 17,225 |
| 60503 | Aurora | 16,660 |
| 60433 | Joliet | 15,485 |
| 60417 | Crete | 15,390 |
| 60410 | Channahon | 13,970 |
| 60442 | Manhattan | 13,135 |
| 60481 | Wilmington | 11,303 |
| 60449 | Monee | 9,564 |
| 60401 | Beecher | 7,833 |
| 60484 | University Park | 6,633 |
| 60468 | Peotone | 5,782 |
| 60408 | Braidwood | 5,307 |
| 60421 | Elwood | 3,850 |