Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
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Washington Zone 4 (Baltimore LATA), MD

NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-954 A WDLWMDWLDS0  9212 VERIZON MARYLAND, INC. 238      

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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