Local Calling Guide

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

NXX: 731

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
443-731 A Port Deposit MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      
443-731 0 Port Deposit MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2024-03-03   
443-731 1 Port Deposit MD BLTMMDCH47Z  420C ARMSTRONG TELECOMMUNICATIONS, INC. - MD 238   2008-08-05   
443-731 2 Port Deposit MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2006-03-05   
443-731 3 Port Deposit MD BLTMMDSN6MD  6119 LEVEL 3 COMMUNICATIONS, LLC - MD 238   2008-11-19   
443-731 4 Port Deposit MD BLTOMDKHDS0  7228 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MD 238   2017-08-03   
443-731 5 Port Deposit MD BLTMMDCH42Z  876D ONVOY, LLC - MD 238   2018-06-16   
443-731 6 Port Deposit MD BLTMMDCH45Z  071F BANDWIDTH.COM CLEC, LLC - MD 238   2008-12-11   
443-731 7 Port Deposit MD BLTMMDCHXVX  321J HD CARRIER LLC 238   2016-05-14   
443-731 8 Port Deposit MD BLTQMD018MD  145J TERRA NOVA TELECOM INC. 238   2024-02-15   
443-731 9 Port Deposit MD BLTMMDFMDS0  7325 TELEPORT COMMUNICATIONS AMERICA, LLC - MD 238      

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

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