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: 312

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-312 A Rockford IL RCFRILRTZMD  224C ONVOY, LLC 360   2024-12-29   
815-312 0 Rockford IL   224C ONVOY, LLC 360   2009-01-29   
815-312 1 Rockford IL   6265 UNITED STATES CELLULAR - IL 360   2026-01-21   
815-312 2 Rockford IL   6265 UNITED STATES CELLULAR - IL 360   2026-01-21   
815-312 3 Rockford IL   6265 UNITED STATES CELLULAR - IL 360   2026-01-21   
815-312 4 Rockford IL   6265 UNITED STATES CELLULAR - IL 360   2026-01-21   
815-312 5 Rockford IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 360   2009-08-29   
815-312 6 Rockford IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 360   2010-02-27   
815-312 7 Rockford IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 360   2010-02-27   
815-312 8 Rockford IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 360   2010-05-28   
815-312 9 Rockford IL   6265 UNITED STATES CELLULAR - IL 360   2026-01-21   

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

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