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: 581

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-581 A Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238      
443-581 0 Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
443-581 1 Chase MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-03-04   
443-581 3 Chase MD BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2024-09-12   
443-581 5 Chase MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-02-24   
443-581 6 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-07-30   
443-581 7 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-07-30   
443-581 8 Chase MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2019-07-06   
443-581 9 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   

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

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