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 BLTMMDSNDS5  4773 XO MARYLAND, LLC 238      
443-581 0 Chase MD   876D ONVOY, LLC - MD 238   2021-03-04   
443-581 1 Chase MD   876D ONVOY, LLC - MD 238   2021-03-04   
443-581 2 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-581 3 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-581 4 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-581 5 Chase MD   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   6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC DBA T-MOBILE USA 238   2019-07-06   
443-581 9 Chase MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2019-04-30   

Last updated: Fri, 01 Jul 2022 02:53:40 UTC

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