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: 361

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-361 A Washington Zone 4 MD LARLMDCC5MD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 236      

Last updated: Sat, 02 May 2026 12:20:53 UTC

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