Local Calling Guide

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NPA: 443 [Rate centres in NPA 443] [Dial plan for NPA 443]

NXX: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-440 A Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-440 0 Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2010-09-10   
443-440 1 Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2010-09-10   
443-440 2 Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2010-09-10   
443-440 3 Annapolis MD BLTMMDSNNMD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2010-11-07   
443-440 4 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-440 5 Annapolis MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2010-06-26   
443-440 6 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238   2010-08-16   
443-440 7 Annapolis MD CLMAMDORAMD  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2011-09-04   
443-440 8 Annapolis MD BLTMMDSNNMD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2011-02-11   
443-440 9 Annapolis MD BLTMMDSNNMD  7591 LEVEL 3 TELECOM OF MARYLAND, LLC - MD 238   2011-02-11   

Last updated: Sat, 01 Aug 2026 03:19:33 UTC

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