Maryland area codes

Maryland has 6 active geographic area codes in this directory: 227, 240, 301, 410, 443 and 667.

Start with the first three digits after +1 on the number you want to check. The codes in this directory are associated with places including Frederick and Baltimore. The listed places are examples, not a complete map of each code’s boundaries.

NANPA groups these codes in shared numbering complexes: 227 / 240 / 301; 410 / 443 / 667. Members can serve overlapping areas; being in the same complex does not necessarily mean identical geographic boundaries.

Open the individual area code to check its local dialing rule. For a phone lookup, enter +1 followed by the three-digit area code and the seven-digit number. A state or area code alone is not enough to look up a particular number.

No. An area code describes a number’s assigned region. People can keep numbers after moving, use them while traveling, or place internet-based calls. Caller ID can also be spoofed, so the code does not confirm the caller’s location or identity.