Boulder County, Colorado ZIP Codes
- ZIP records
18 - Cities represented
12 - Sum of listed ZIP population estimates
285,786
Population sum includes positive estimates in these ZIP records; it is not an official county population.
Top ZIP Codes by Population
| Rank | ZIP Code | City | Population estimate |
|---|---|---|---|
| 1 | 80501 | Longmont | 44,147 |
| 2 | 80503 | Longmont | 35,846 |
| 3 | 80027 | Louisville | 34,127 |
| 4 | 80026 | Lafayette | 32,701 |
| 5 | 80302 | Boulder | 29,569 |
| 6 | 80304 | Boulder | 25,383 |
| 7 | 80301 | Boulder | 25,007 |
| 8 | 80303 | Boulder | 24,996 |
| 9 | 80305 | Boulder | 16,291 |
| 10 | 80310 | Boulder | 7,692 |
Cities in Boulder County
- Allenspark
- Boulder
- Eldorado Springs
- Jamestown
- Lafayette
- Longmont
- Louisville
- Lyons
- Nederland
- Niwot
- Pinecliffe
- Ward
ZIP Directory
- ZIP 80025
- ZIP 80026
- ZIP 80027
- ZIP 80301
- ZIP 80302
- ZIP 80303
- ZIP 80304
- ZIP 80305
- ZIP 80310
- ZIP 80455
- ZIP 80466
- ZIP 80471
- ZIP 80481
- ZIP 80501
- ZIP 80503
- ZIP 80510
- ZIP 80540
- ZIP 80544
Browse all ZIP data for Colorado
Methodology: Records are grouped by the source file's listed county and state. Population sums add positive ZIP-level estimates and are not official county totals; city counts use distinct city labels in the source.