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: 538

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-538 A Columbia MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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