| Zip Code | Area Code | City | County | Centroid | Other Information |
| 20880 | 301 | Washington Grove | Montgomery | (39.1398, -77.1756) | Observes Daylight Savings Time |
| 20855 | | Derwood | Montgomery | (39.11733, -77.1610916) | |
| 20850 | 301 | Rockville | Montgomery | (39.0873, -77.1745) | Observes Daylight Savings Time |
| 20855 | 301 | Rockville | Montgomery | (39.145, -77.1376) | Observes Daylight Savings Time |
| 20849 | 301 | Rockville | Montgomery | (39.084, -77.1537) | Observes Daylight Savings Time |
| 20847 | 301 | Rockville | Montgomery | (39.0838, -77.153) | Observes Daylight Savings Time |
| 20877 | | Montgomery Village | Montgomery | (39.1767734, -77.1952597) | |
| 20878 | | North Potomac | Montgomery | (39.096432, -77.244955) | |
| 20857 | 301 | Rockville | Montgomery | (39.0812, -77.1539) | Observes Daylight Savings Time |
| 20851 | 301 | Rockville | Montgomery | (39.0761, -77.1247) | Observes Daylight Savings Time |
| 20876 | 301 | Germantown | Montgomery | (39.1912, -77.2347) | Observes Daylight Savings Time |
| 20848 | 301 | Rockville | Montgomery | (39.0753, -77.1165) | Observes Daylight Savings Time |
| 20875 | 301 | Germantown | Montgomery | (39.1782, -77.2607) | Observes Daylight Savings Time |
| 20853 | 301 | Rockville | Montgomery | (39.0958, -77.0953) | Observes Daylight Savings Time |
| 20874 | 301 | Germantown | Montgomery | (39.1397, -77.291) | Observes Daylight Savings Time |
| 20908 | 301 | Silver Spring | Montgomery | (39.1035, -77.0763) | Observes Daylight Savings Time |
| 20852 | 301 | Rockville | Montgomery | (39.0521, -77.119) | Observes Daylight Savings Time |
| 20832 | 301 | Olney | Montgomery | (39.151, -77.0738) | Observes Daylight Savings Time |
| 20879 | | Laytonsville | Montgomery | (39.2120504, -77.1427587) | |
| 20830 | 301 | Olney | Montgomery | (39.1577, -77.0738) | Observes Daylight Savings Time |
| 20916 | 301 | Silver Spring | Montgomery | (39.083, -77.0785) | Observes Daylight Savings Time |
| 20895 | | North Bethesda | Montgomery | (39.0445535, -77.1188678) | |
| 20859 | 301 | Potomac | Montgomery | (39.0257, -77.1977) | Observes Daylight Savings Time |
| 20854 | 301 | Potomac | Montgomery | (39.0287, -77.2409) | Observes Daylight Savings Time |
| 20058 | 202 | Washington | District of Columbia | (39.0259, -77.138) | Observes Daylight Savings Time |