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: 656

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-656 A Columbia MD HNVAMDBHAMD  3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 0 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 1 Columbia MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-22   
443-656 2 Columbia MD BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2021-01-27   
443-656 3 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 4 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 5 Columbia MD BLTMMDCHXMX  506J TWILIO INTERNATIONAL INC 238   2020-12-26   
443-656 6 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 7 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 8 Columbia MD   3910 CAVALIER TELEPHONE MID-ATLANTIC, LLC - MD 238      
443-656 9 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-11   

Last updated: Wed, 01 Jun 2022 03:09:23 UTC

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