Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: WASHDCRKDS3

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
202-464 A Washington Zone 1 DC 4937 ALLEGIANCE TELECOM OF DC, INC. 236      
240-223 A Washington Zone 2 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-243 A Gaithersburg MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-247 A Washington Zone 3 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-260 A Washington Zone 14 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-268 A Washington Zone 10 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-290 A Washington Zone 11 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-306 A Gaithersburg MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-548 A Washington Zone 14 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-553 A Washington Zone 13 MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-554 A Laurel MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
240-559 A Ashton MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      
443-753 A Waterloo (Washington DC LATA) MD 8992 ALLEGIANCE TELECOM OF MARYLAND, INC. 236      

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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