| District of Maryland area codes: 443 | |
|---|---|
| Country | United States |
| State/Province | Maryland |
| Major City | Baltimore |
| Time Zone | Eastern |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 443-812 | Howard | Columbia, MD | Cellco Partnership DBA Verizon Wireless |
| 443-813 | Baltimore City | Baltimore, MD | Cellco Partnership DBA Verizon Wireless |
| 443-814 | Baltimore City | Baltimore, MD | Cellco Partnership DBA Verizon Wireless |
| 443-815 | Baltimore City | Baltimore, MD | Xo Maryland |
| 443-816 | Anne Arundel | Severna Park, MD | Allegiance Telecom |
| 443-817 | Baltimore City | Baltimore, MD | Allegiance Telecom |
| 443-818 | Anne Arundel | Pasadena, MD | Level 3 Communications |
| 443-820 | Baltimore City | Baltimore, MD | Paetec Communications |
| 443-821 | Carroll | Westminster, MD | Sprint Spectrum L.p. |
| 443-822 | Anne Arundel | Annapolis, MD | Sprint Spectrum L.p. |
| 443-823 | Baltimore | Towson, MD | Cellco Partnership DBA Verizon Wireless |
| 443-824 | Baltimore | Towson, MD | Omnipoint Communications Cap Operations |
| 443-825 | Baltimore City | Baltimore, MD | Omnipoint Communications Cap Operations |
| 443-826 | Baltimore City | Baltimore, MD | Cellco Partnership DBA Verizon Wireless |
| 443-827 | Baltimore City | Baltimore, MD | Cellco Partnership DBA Verizon Wireless |
| 443-828 | Howard | Ellicott City, MD | Cavalier Telephone Mid-atlantic |
| 443-829 | Baltimore City | Baltimore, MD | Sprint Spectrum L.p. |
| 443-830 | Baltimore | Catonsville, MD | Cavalier Telephone Mid-atlantic |
| 443-831 | Baltimore City | Baltimore, MD | New Cingular Wireless PCS - DC |
| 443-832 | Baltimore City | Baltimore, MD | Level 3 Communications |
There are 781 prefixes, In the code area, the major cities are Annapolis, MD;Arbutus, MD;Arnold, MD;Baltimore, MD. The major city is Baltimore.