Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Washington Zone 13, MD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
301-993 A CLPKMDBWDS0  9212 VERIZON MARYLAND, INC. 236      

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

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