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: 971

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-971 A Frederick MD FRDRMDFRXKX  508J CENTURYLINK COMMUNICATIONS, LLC 240      
240-971 0 Frederick MD   073H TELNYX LLC 240   2017-08-08   
240-971 1 Frederick MD   551G NUSO, LLC 240   2018-10-14   
240-971 2 Frederick MD   551G NUSO, LLC 240   2018-11-07   
240-971 3 Frederick MD   551G NUSO, LLC 240   2018-11-07   
240-971 4 Frederick MD   551G NUSO, LLC 240   2018-11-07   
240-971 5 Frederick MD   551G NUSO, LLC 240   2018-11-07   
240-971 6 Frederick MD   5562 METROPCS, INC. 240   2018-04-09   
240-971 7 Frederick MD   508J CENTURYLINK COMMUNICATIONS, LLC 240   2016-10-01   
240-971 8 Frederick MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2018-02-05   
240-971 9 Frederick MD   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 240   2018-02-05   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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