Local Calling Guide

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Search area code/prefix (NPA/NXX)
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NPA: 317 [Rate centres in NPA 317] [Dial plan for NPA 317]

NXX: 421

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
317-421 A Shelbyville IN SHVLIN01DS1  9325 INDIANA BELL TEL CO INC 336      
317-421 0 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 1 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 2 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 3 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 4 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 5 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 6 Shelbyville IN   829J PAETEC ITEL, LLC 336   2012-07-24   
317-421 7 Shelbyville IN   097D ONVOY, LLC - IN 336   2012-11-12   
317-421 8 Shelbyville IN   9325 INDIANA BELL TEL CO INC 336      
317-421 9 Shelbyville IN   6725 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IN 336   2013-03-20   

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

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