County · Maryland · United States
Frederick County ZIP codes
27 ZIP codes · 23 cities · FIPS 24021
Key facts
- State
- Maryland (MD)
- FIPS code
- 24021
- Population
- 280,341
- Median household income
- $120,458
- Median age
- 38.9
- Land area
- 660.6 sq mi (1,710.9 km²)
- Population density
- 424 / sq mi
- Area codes
- 227, 240, 301
Cities and ZIP codes in Frederick County (23)
About this page
County figures are Census county-level values (ACS 5-year); the ZIP list shows the ZIPs whose primary county this is — a ZIP on a border can also serve neighbouring counties.
Sources: U.S. Census Bureau (2020 county relationship file, ACS 5-year) · GeoNames. Methodology.