Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

NXX:

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-521 A Chicago Zone 01-Lakeshore IL CHCGILCLGMD  7421 AT&T LOCAL 358      
312-521 0 Chicago Zone 01-Lakeshore IL   984E BANDWIDTH.COM CLEC, LLC - IL 358   2010-03-04   
312-521 1 Chicago Zone 01-Lakeshore IL   063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358   2002-11-16   
312-521 2 Chicago Zone 01-Lakeshore IL   7721 BROADWING COMMUNICATIONS, LLC - IL 358   2002-11-20   
312-521 3 Chicago Zone 01-Lakeshore IL   6664 SPRINT SPECTRUM L.P. 358   2004-03-01   
312-521 4 Chicago Zone 01-Lakeshore IL   4717 PAETEC COMMUNICATIONS, INC. - IL 358   2009-04-08   
312-521 5 Chicago Zone 01-Lakeshore IL   5447 ACCESS ONE, INC. - IL 358   2009-02-25   
312-521 6 Chicago Zone 01-Lakeshore IL   7421 AT&T LOCAL 358      
312-521 7 Chicago Zone 01-Lakeshore IL   4604 FIRST COMMUNICATIONS LLC - IL 358   2003-10-22   
312-521 8 Chicago Zone 01-Lakeshore IL   7765 OVATION COMMUNICATIONS OF ILLINOIS, INC. 358   2013-08-23   
312-521 9 Chicago Zone 01-Lakeshore IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2011-02-07   

Last updated: Sun, 10 Nov 2019 13:49:34 UTC

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