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: 658

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-658 A Gaithersburg MD WASHDC125MD  197D VONAGE AMERICA LLC 236      
240-658 0 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 1 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 2 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 3 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 4 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 5 Gaithersburg MD   5562 METROPCS, INC. 236   2019-11-29   
240-658 6 Gaithersburg MD   197D VONAGE AMERICA LLC 236   2019-01-25   
240-658 7 Gaithersburg MD   624H ONVOY SPECTRUM, LLC 236   2021-05-21   
240-658 8 Gaithersburg MD   876D ONVOY, LLC - MD 236   2021-02-18   
240-658 9 Gaithersburg MD   876D ONVOY, LLC - MD 236   2021-02-18   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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