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 CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-640 0 Bel Air MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-640 1 Bel Air MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-640 2 Bel Air MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-640 3 Bel Air MD CLMAMDJTAMD  2589 US LEC OF MARYLAND, INC. 238      
443-640 4 Bel Air MD BLTMMDCHXFX  318J COMCAST IP PHONE, LLC 238      
443-640 5 Bel Air MD BLTOMDKHBMD  6395 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MD 238      
443-640 6 Bel Air MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238      
443-640 7 Bel Air MD CLMAMDORGT0  4036 NEW CINGULAR WIRELESS PCS, LLC - DC 238      
443-640 8 Bel Air MD BLTMMDCH40Z  6855 OMNIPOINT COMMUNICATIONS CAP OPERATIONS, LLC 238      
443-640 9 Bel Air MD BLTMMDCHX7X  073H TELNYX LLC 238      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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