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: 363

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-363 A Severn MD BLTMMD91GT0  2593 CORE COMMUNICATIONS, INC.- MD 238      
443-363 0 Severn MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-14   
443-363 1 Severn MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-14   
443-363 2 Severn MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-10-23   
443-363 3 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2019-03-31   
443-363 4 Severn MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-363 5 Severn MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-04-14   
443-363 6 Severn MD   2593 CORE COMMUNICATIONS, INC.- MD 238   2018-06-16   
443-363 7 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2018-10-05   
443-363 8 Severn MD BLTMMDCHX7X  073H TELNYX LLC 238   2017-04-25   
443-363 9 Severn MD BLTMMDCH40Z  5562 METROPCS, INC. 238   2020-12-31   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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