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: 370

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-370 A Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-370 0 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-370 1 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-31   
443-370 2 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-31   
443-370 3 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-31   
443-370 4 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-02-18   
443-370 5 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-31   
443-370 6 Annapolis MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2005-01-31   
443-370 7 Annapolis MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-09-01   
443-370 8 Annapolis MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2005-09-20   
443-370 9 Annapolis MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2006-02-03   

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

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