Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 301 [Rate centres in NPA 301] [Dial plan for NPA 301]

NXX: 584

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-584 A Washington Zone 12 MD VINNVACB2MD  8697 BALTIMORE-WASHINGTON TELEPHONE (BWT) 236      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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