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: 597

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-597 A Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
240-597 0 Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
240-597 1 Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
240-597 2 Gaithersburg MD SLSPMD913MD  939H COMMIO, LLC 236   2021-07-12   
240-597 3 Gaithersburg MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-06-27   
240-597 4 Gaithersburg MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-06-27   
240-597 5 Gaithersburg MD   2593 CORE COMMUNICATIONS, INC.- MD 236   2019-06-27   
240-597 6 Gaithersburg MD BTVLMD18G00  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2019-07-13   
240-597 7 Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236   2019-12-28   
240-597 8 Gaithersburg MD BTVLMD18G00  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 236   2022-06-14   
240-597 9 Gaithersburg MD SLSPMD91DS0  568G PEERLESS NETWORK OF MARYLAND, LLC 236      

Last updated: Tue, 16 Apr 2024 01:38:01 UTC

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