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: 504

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-504 A Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236      
240-504 0 Washington Zone 3 MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-10-09   
240-504 1 Washington Zone 3 MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-12-03   
240-504 2 Washington Zone 3 MD BTVLMD18GT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2023-12-03   
240-504 4 Washington Zone 3 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2011-11-18   

Last updated: Fri, 22 Mar 2024 03:02:44 UTC

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