Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 423 [Rate centres in NPA 423] [Dial plan for NPA 423]

NXX: 640

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-640 A Sneedville TN KNVLTNMAYGX  7421 AT&T - LOCAL 474      
423-640 6 Sneedville TN KNVLTNMA54Z  114F TELEPORT COMMUNICATIONS AMERICA, LLC - TN 474   2020-08-27   
423-640 7 Sneedville TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2021-06-25   
423-640 8 Sneedville TN KNVLTNMA49Z  525E ONVOY, LLC - TN 474   2021-01-11   
423-640 9 Sneedville TN KNVLTNMAYGX  7421 AT&T - LOCAL 474   2020-06-08   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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