| District of Maryland area codes: 301 | |
|---|---|
| Country | United States |
| State/Province | Maryland |
| Major City | Baltimore |
| Time Zone | Eastern (UTC-05:00) |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 301-200 | Charles | Indian Head, MD | Bandwidth.com Clec |
| 301-202 | Montgomery | Chevy Chase, MD | New Cingular Wireless PCS - DC |
| 301-203 | Prince Georges | Fort Washington, MD | Verizon Maryland |
| 301-204 | Montgomery | Bethesda, MD | New Cingular Wireless PCS - DC |
| 301-205 | Anne Arundel | Edgewater, MD | Verizon Maryland |
| 301-206 | Prince Georges | Laurel, MD | Verizon Maryland |
| 301-207 | Prince Georges | Greenbelt, MD | Usa Mobility Wireless |
| 301-208 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-209 | Prince Georges | Hyattsville, MD | Verizon Maryland |
| 301-210 | Prince Georges | Beltsville, MD | Verizon Maryland |
| 301-212 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-213 | Prince Georges | Beltsville, MD | Sprint Spectrum L.p. |
| 301-214 | Montgomery | Rockville, MD | Verizon Maryland |
| 301-215 | Montgomery | Chevy Chase, MD | Verizon Maryland |
| 301-216 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-217 | Montgomery | Rockville, MD | Verizon Maryland |
| 301-218 | Prince Georges | Bowie, MD | Verizon Maryland |
| 301-219 | Montgomery | Bethesda, MD | New Cingular Wireless PCS - DC |
| 301-220 | Prince Georges | Greenbelt, MD | Verizon Maryland |
| 301-221 | Montgomery | Bethesda, MD | New Cingular Wireless PCS - DC |
There are 775 prefixes, In the code area, the major cities are Aspen Hill, MD;Bethesda, MD;Bowie, MD;Chillum, MD;. The major city is Baltimore.