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 PIVLMDPKXGX  829J PAETEC ITEL, LLC 238   2025-04-01   
443-656 0 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 1 Columbia MD BLTMMDCHXUX  624H ONVOY SPECTRUM, LLC 238   2021-05-22   
443-656 2 Columbia MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-656 3 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 4 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 5 Columbia MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2025-01-08   
443-656 6 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 7 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 8 Columbia MD PIVLMDPKXGX  829J PAETEC ITEL, LLC 238      
443-656 9 Columbia MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2021-07-11   

Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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