Maryland
- ZIP codes
- 605
- Postal place names
- 431
- County associations
- 24
Overview
Maryland surrounds much of Chesapeake Bay, stretching from Atlantic beaches through the Piedmont to the Appalachian mountains. Annapolis is the state capital. Other cities include Baltimore, Frederick.
- State capital
- Annapolis
Population overview
- Estimated population
- 6,265,347
- Reference year
- 2025
Population of the matched statistical area, not a ZIP delivery area.
Map & location
Scroll or pinch to zoom · drag to move · select a state or prefix to open it
Keyboard: arrows pan, + and − zoom, Home resets; Tab reaches map links.
Dots summarize approximate ZIP locations grouped by state and three-digit prefix; they are not official delivery boundaries. Colors follow the first digit. Not every number in a displayed range is assigned. Alaska and island insets are relocated and use different scales.
Locations use available coordinates, not delivery boundaries. The simplified world outline may omit small islands; postal associations do not imply administrative ownership.
County outlines are simplified 2017 Census reference geography, not current legal or ZIP delivery boundaries. Highlighting follows postal associations.
No reliable coordinates are available for this postal region.
ZIP directory
Page 1 / 11Postal details & data notes
- ZIPs with coordinates
- 605
Common three-digit prefixes
Counts refer to this place; links explore the full prefix nationally. Endpoints do not imply every intervening ZIP exists. Postal names are not a count of incorporated municipalities.
ZIP codes organize mail delivery, not administrative boundaries. A code can have several city or county associations. Coordinates are approximate; verify delivery addresses with your carrier. Read the guide ↗