Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 815 [Rate centres in NPA 815] [Dial plan for NPA 815]

NXX: 491

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-491 A Rockford IL RCFRILRTXKX  551G NUSO, LLC 360      
815-491 0 Rockford IL   6529 T-MOBILE USA, INC. 360   2014-03-27   
815-491 1 Rockford IL   551G NUSO, LLC 360   2013-05-08   
815-491 2 Rockford IL   6529 T-MOBILE USA, INC. 360   2014-03-27   
815-491 3 Rockford IL   6529 T-MOBILE USA, INC. 360   2014-03-27   
815-491 4 Rockford IL   6529 T-MOBILE USA, INC. 360   2014-03-27   
815-491 5 Rockford IL   6529 T-MOBILE USA, INC. 360   2014-03-27   
815-491 6 Rockford IL   224C ONVOY, LLC 360   2015-02-23   
815-491 7 Rockford IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 360   2015-06-11   
815-491 8 Rockford IL   224C ONVOY, LLC 360   2016-02-29   
815-491 9 Rockford IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 360   2015-02-15   

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

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