Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 623 [Rate centres in NPA 623] [Dial plan for NPA 623]

NXX: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
623-440 A Phoenix AZ PHNXAZMAX1Z  318J COMCAST IP PHONE, LLC 666      
623-440 0 Phoenix AZ   073H TELNYX LLC 666   2018-07-13   
623-440 1 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 2 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 3 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 4 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 5 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 6 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 7 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 8 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   
623-440 9 Phoenix AZ   318J COMCAST IP PHONE, LLC 666   2018-07-09   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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