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: 564

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-564 A Sterling IL STNGILSIDS0  9329 ILLINOIS BELL TEL CO 364      
815-564 0 Sterling IL   9329 ILLINOIS BELL TEL CO 364      
815-564 1 Sterling IL   9329 ILLINOIS BELL TEL CO 364      
815-564 2 Sterling IL   6115 LEVEL 3 COMMUNICATIONS, LLC - IL 364   2006-11-01   
815-564 3 Sterling IL   6529 T-MOBILE USA, INC. 364   2018-03-24   
815-564 4 Sterling IL   9329 ILLINOIS BELL TEL CO 364      
815-564 5 Sterling IL   9329 ILLINOIS BELL TEL CO 364      
815-564 6 Sterling IL   9329 ILLINOIS BELL TEL CO 364      
815-564 7 Sterling IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 364      
815-564 8 Sterling IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 364      
815-564 9 Sterling IL   9329 ILLINOIS BELL TEL CO 364      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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