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: 728

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-728 A Washington Zone 10 MD WASHDC125MD  197D VONAGE AMERICA LLC 236      
240-728 0 Washington Zone 10 MD WASHDC125MD  197D VONAGE AMERICA LLC 236   2020-06-26   
240-728 1 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2021-01-01   
240-728 2 Washington Zone 10 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-10-17   
240-728 3 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2021-01-01   
240-728 4 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2021-01-01   
240-728 5 Washington Zone 10 MD WASHDC125MD  197D VONAGE AMERICA LLC 236   2020-06-26   
240-728 6 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2021-01-01   
240-728 7 Washington Zone 10 MD VINNVACBDS0  876D ONVOY, LLC - MD 236   2020-10-17   
240-728 8 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2020-09-08   
240-728 9 Washington Zone 10 MD BTVLMD12CMA  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 236   2020-09-08   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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