| 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 |
|---|---|---|---|
| 301-965 | Prince Georges | Hyattsville, MD | Mcimetro Access Transmission Services LLC |
| 301-966 | Prince Georges | Hyattsville, MD | Mcimetro Access Transmission Services LLC |
| 301-967 | Prince Georges | Suitland, MD | Verizon Maryland |
| 301-968 | Montgomery | Bethesda, MD | Mci Worldcom Communications |
| 301-969 | Frederick | Brunswick, MD | Comcast Phone Of Northern Maryland |
| 301-970 | Anne Arundel | Annapolis, MD | Verizon Maryland |
| 301-971 | Prince Georges | Oxon Hill, MD | Starpower Communications |
| 301-972 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-973 | Prince Georges | Glenn Dale, MD | Verizon Maryland |
| 301-974 | Prince Georges | Laurel, MD | Starpower Communications |
| 301-975 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-976 | Baltimore-washington Telephone (bwt) | ||
| 301-977 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-978 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-979 | Montgomery | Gaithersburg, MD | Verizon Maryland |
| 301-980 | Montgomery | Silver Spring, MD | Cellco Partnership DBA Verizon Wireless |
| 301-981 | Prince Georges | Mount Rainier, MD | Tw Telecom Of Maryland LLC |
| 301-982 | Prince Georges | Greenbelt, MD | Verizon Maryland |
| 301-983 | Montgomery | Bethesda, MD | Verizon Maryland |
| 301-984 | Montgomery | Rockville, MD | Verizon Maryland |
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.