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: 858

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-858 A Baltimore MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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