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: 603

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
423-603 A Fork Ridge TN WNCHKYMAXMY  516C AT&T CORP. 466      
423-603 0 Fork Ridge TN   6214 NEW CINGULAR WIRELESS PCS, LLC - GA 466   2019-10-18   
423-603 1 Fork Ridge TN   6214 NEW CINGULAR WIRELESS PCS, LLC - GA 466   2019-10-18   
423-603 2 Fork Ridge TN   525E ONVOY, LLC - TN 466   2020-07-01   
423-603 3 Fork Ridge TN   525E ONVOY, LLC - TN 466   2020-07-01   
423-603 4 Fork Ridge TN   525E ONVOY, LLC - TN 466   2020-07-01   
423-603 5 Fork Ridge TN   525E ONVOY, LLC - TN 466   2020-07-01   
423-603 6 Fork Ridge TN   525E ONVOY, LLC - TN 466   2019-08-29   
423-603 7 Fork Ridge TN   516C AT&T CORP. 466   2014-01-29   
423-603 8 Fork Ridge TN   073H TELNYX LLC 466   2021-01-23   
423-603 9 Fork Ridge TN   624H ONVOY SPECTRUM, LLC 466   2021-02-24   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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