Area code 410 is a telephone area code in the North American Numbering Plan. It covers the eastern part of Maryland, including cities like Baltimore, Annapolis, and Ocean City. Area code 410 was created in 1991 when it was split from area code 301. To meet the increasing demand for phone numbers, area code 410 was overlaid with area codes 443 and 667 in 1997 and 2012, respectively.[1]

References

change
  1. "Maryland's new 667 area code goes into effect in 2012".