ZIP Codes are postal codes used by the USPS to identify specific geographic locations and improve the efficiency of the mail delivery system in the USA. In maryland, ZIP Codes are used to ensure that mail is delivered to the correct location within the state. The first digit of a ZIP Code indicates a general region, the second and third digits indicate a specific region within that region, and the fourth and fifth digits indicate a specific delivery area or post office. ZIP Codes are an essential part of the mail delivery system in maryland.
| Post Office | Silver Spring |
| Division | Montgomery |
| Zip code | 20906 |
| Post Office | Parkville |
| Division | Baltimore |
| Zip code | 21234 |
| Post Office | Gaithersburg |
| Division | Montgomery |
| Zip code | 20878 |
| Post Office | Hagerstown |
| Division | Washington |
| Zip code | 21740 |
| Post Office | Germantown |
| Division | Montgomery |
| Zip code | 20874 |
| Post Office | Pasadena |
| Division | Anne Arundel |
| Zip code | 21122 |
"Explore Maryland ZIP Codes: A Guide to the Postal Codes of the Maryland State"