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: 433

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-433 A Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-433 0 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-433 1 Annapolis MD   829J PAETEC ITEL, LLC 238   2005-10-07   
443-433 2 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2006-03-02   
443-433 3 Annapolis MD   829J PAETEC ITEL, LLC 238   2005-04-18   
443-433 4 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-433 5 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-433 6 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2006-03-02   
443-433 7 Annapolis MD BLTMMDCHXNX  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 238      
443-433 8 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2006-03-02   
443-433 9 Annapolis MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2011-08-19   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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