Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 479

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-479 A Waterloo (Washington DC LATA) MD LARLMDDYDS0  9212 VERIZON MARYLAND, INC. 236      

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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