| Zip Code | City | Population ↓ |
|---|---|---|
| 33040 | Key West | 35,429 |
| 33037 | Key Largo | 14,770 |
| 33050 | Marathon | 10,561 |
| 33042 | Summerland Key | 6,441 |
| 33070 | Tavernier | 5,768 |
| 33043 | Big Pine Key | 4,298 |
| 33036 | Islamorada | 3,777 |
| 33051 | Key Colony Beach | 511 |
| 33001 | Long Key | 250 |
The data shown reflect ZCTAs from the US Census. As of 2025, there are 9 ZCTAs in Monroe County, Florida (US Census).