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: 594

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-594 A Dayton TN CHTGTNMAX9X  7421 AT&T - LOCAL 472      
423-594 0 Dayton TN   525E ONVOY, LLC - TN 472   2019-04-27   
423-594 1 Dayton TN   525E ONVOY, LLC - TN 472   2016-04-11   
423-594 2 Dayton TN   525E ONVOY, LLC - TN 472   2016-04-11   
423-594 3 Dayton TN   7278 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - TN 472   2016-10-16   
423-594 4 Dayton TN   4645 ELECTRIC POWER BOARD OF CHATTANOOGA 472   2019-08-11   
423-594 5 Dayton TN   6214 NEW CINGULAR WIRELESS PCS, LLC - GA 472   2019-08-18   
423-594 6 Dayton TN   6214 NEW CINGULAR WIRELESS PCS, LLC - GA 472   2019-08-18   
423-594 7 Dayton TN   124F BANDWIDTH.COM CLEC, LLC - TN 472   2025-10-10   
423-594 8 Dayton TN   525E ONVOY, LLC - TN 472   2019-04-27   
423-594 9 Dayton TN   7421 AT&T - LOCAL 472   2009-11-19   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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