Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 240 [Rate centres in NPA 240] [Dial plan for NPA 240]

NXX: 304

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-304 A Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
240-304 0 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2003-05-14   
240-304 1 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2003-05-14   
240-304 2 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2003-05-14   
240-304 3 Washington Zone 5 MD WASHDC12DS6  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2012-09-15   
240-304 4 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2004-05-13   
240-304 5 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2004-05-13   
240-304 6 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2003-02-26   
240-304 7 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2002-10-17   
240-304 8 Washington Zone 5 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2002-10-17   
240-304 9 Washington Zone 5 MD BTVLMD12CMA  5562 METROPCS, INC. 236   2004-02-16   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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