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: 598

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-598 A Washington Zone 12 MD SLSPMDNBDS0  9212 VERIZON MARYLAND, INC. 236      

Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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