Zip Code | City | Population |
|---|---|---|
| 80634 | Greeley | 62,001 |
| 80504 | Longmont | 60,527 |
| 80631 | Greeley | 54,346 |
| 80550 | Windsor | 41,428 |
| 80516 | Erie | 34,998 |
| 80620 | Evans | 21,048 |
| 80534 | Johnstown | 19,368 |
| 80621 | Fort Lupton | 13,863 |
| 80543 | Milliken | 9,109 |
| 80615 | Eaton | 8,840 |
| 80514 | Dacono | 6,275 |
| 80530 | Frederick | 5,774 |
| 80542 | Mead | 5,179 |
| 80642 | Hudson | 5,146 |
| 80645 | La Salle | 4,810 |
| 80651 | Platteville | 4,441 |
| 80643 | Keenesburg | 3,989 |
| 80610 | Ault | 3,172 |
| 80644 | Kersey | 2,604 |
| 80650 | Pierce | 1,896 |
| 80520 | Firestone | 1,736 |
| 80648 | Nunn | 1,296 |
| 80623 | Gilcrest | 1,082 |
| 80611 | Briggsdale | 809 |
| 80624 | Gill | 681 |
| 80729 | Grover | 403 |
| 80649 | Orchard | 347 |
| 80652 | Roggen | 342 |
| 80612 | Carr | 309 |
| 80546 | Severance | 234 |
| 80742 | New Raymer | 224 |
| 80622 | Galeton | 202 |
| 80754 | Stoneham | 138 |
| 80732 | Hereford | 24 |
| 80646 | Lucerne | 0 |