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: 558

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-558 A Rockford IL RCFRILRTXGY  6265 UNITED STATES CELLULAR - IL 360      
815-558 0 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 1 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 2 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 3 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 4 Rockford IL   6529 T-MOBILE USA, INC. 360   2011-10-20   
815-558 5 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 6 Rockford IL   6529 T-MOBILE USA, INC. 360   2011-10-20   
815-558 7 Rockford IL   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 360   2012-02-19   
815-558 8 Rockford IL   6265 UNITED STATES CELLULAR - IL 360      
815-558 9 Rockford IL   6529 T-MOBILE USA, INC. 360   2011-10-20   

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

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