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: 921

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
815-921 A Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 0 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 1 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 2 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 3 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 4 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 5 Rockford IL   321J HD CARRIER LLC 360   2026-03-14   
815-921 6 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 8 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      
815-921 9 Rockford IL LVPKILRNDS0  9329 ILLINOIS BELL TEL CO 360      

Last updated: Sat, 21 Mar 2026 23:53:39 UTC

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