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: 484

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-484 A Washington Zone 4 MD ARTNVAARXDY  318J COMCAST IP PHONE, LLC 236      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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