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: 855

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
301-855 A Washington Zone 15 (Baltimore LATA) MD NRBHMDNEDS0  9212 VERIZON MARYLAND, INC. 238      

Last updated: Sat, 05 Apr 2025 03:03:23 UTC

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