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: 640

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-640 A Bel Air MD CLMAMDJTDS0  2589 US LEC OF MARYLAND, INC. 238      
443-640 0 Bel Air MD CLMAMDJTDS0  2589 US LEC OF MARYLAND, INC. 238      
443-640 1 Bel Air MD CLMAMDJTDS0  2589 US LEC OF MARYLAND, INC. 238      
443-640 2 Bel Air MD CLMAMDJTDS0  2589 US LEC OF MARYLAND, INC. 238      
443-640 3 Bel Air MD CLMAMDJTDS0  2589 US LEC OF MARYLAND, INC. 238      
443-640 4 Bel Air MD BLTMMDCHXFX  318J COMCAST IP PHONE LLC 238   2008-04-30   
443-640 5 Bel Air MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238   2009-02-02   
443-640 6 Bel Air MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-09-08   
443-640 7 Bel Air MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238   2012-03-16   
443-640 8 Bel Air MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238   2008-04-21   
443-640 9 Bel Air MD   073H TELNYX LLC 238   2021-03-04   

Last updated: Tue, 04 May 2021 15:04:27 UTC

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