Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: RKVLMDMRRS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
301-443 A Washington Zone 11 MD 9212 VERIZON MARYLAND, INC. 236      

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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