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: 250

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
240-250 A Brandywine MD WASHDC12DS6  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
240-250 0 Brandywine MD WASHDC12DS6  568G PEERLESS NETWORK OF MARYLAND, LLC 236      
240-250 1 Brandywine MD   876D ONVOY, LLC - MD 236   2026-09-05   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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