| 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 |
|---|---|---|---|
| 301-985 | Prince Georges | Hyattsville, MD | Verizon Maryland |
| 301-986 | Montgomery | Chevy Chase, MD | Verizon Maryland |
| 301-987 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-988 | Washington | Hagerstown, MD | Uscoc Of Cumberland DBA United States Cel Md |
| 301-989 | Montgomery | Silver Spring, MD | Verizon Maryland |
| 301-990 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-991 | Washington | Hagerstown, MD | Sprint Spectrum L.p. |
| 301-992 | Washington | Hagerstown, MD | Sprint Spectrum L.p. |
| 301-993 | Prince Georges | Greenbelt, MD | Verizon Maryland |
| 301-994 | Saint Marys | Valley Lee, MD | Verizon Maryland |
| 301-995 | Saint Marys | Patuxent River, MD | Verizon Maryland |
| 301-996 | Prince Georges | Beltsville, MD | Sprint Spectrum L.p. |
| 301-997 | Saint Marys | Leonardtown, MD | Verizon Maryland |
| 301-998 | Montgomery | Rockville, MD | Verizon Maryland |
| 301-555 | Used in movie | Indian Head, MD | Used in movie |
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.