| District of Maryland area codes: 443 | |
|---|---|
| Country | United States |
| State/Province | Maryland |
| Major City | Baltimore |
| Time Zone | Eastern |
| Prefix | County | Primary City | Company |
|---|---|---|---|
| 443-322 | Baltimore | Towson, MD | Cavalier Telephone Mid-atlantic |
| 443-323 | Dorchester | Rhodesdale, MD | Cavalier Telephone (mid-atlantic) |
| 443-324 | Baltimore City | Baltimore, MD | Sprint Spectrum L.p. |
| 443-325 | Howard | Ellicott City, MD | Cavalier Telephone Mid-atlantic |
| 443-326 | Baltimore City | Baltimore, MD | New Cingular Wireless PCS - DC |
| 443-327 | Harford | Aberdeen, MD | Cavalier Telephone Mid-atlantic |
| 443-328 | Carroll | Sykesville, MD | Ctc Communications Corp. |
| 443-329 | Howard | Jessup, MD | Global Crossing Local Services-md |
| 443-330 | Baltimore City | Baltimore, MD | Cavalier Telephone Mid-atlantic |
| 443-331 | Carroll | Taneytown, MD | Ctc Communications Corp. |
| 443-332 | Anne Arundel | Crofton, MD | Cavalier Telephone Mid-atlantic |
| 443-333 | Anne Arundel | Annapolis, MD | Leap Wireless Intl DBA Cricket Comm |
| 443-334 | Baltimore | Towson, MD | Allegiance Telecom |
| 443-335 | Baltimore City | Brooklyn, MD | Xo Maryland |
| 443-336 | Anne Arundel | Annapolis, MD | Sprint Spectrum L.p. |
| 443-337 | Baltimore | Sparrows Point, MD | Xo Maryland |
| 443-338 | Baltimore | Sparks Glencoe, MD | Ctc Communications Corp. |
| 443-339 | Anne Arundel | Sherwood Forest, MD | Ctc Communications Corp. |
| 443-340 | Carroll | Westminster, MD | Cellco Partnership DBA Verizon Wireless |
| 443-341 | 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.