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: 239

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-239 A Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 0 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-239 1 Chicago Zone 01-Canal IL   829J PAETEC ITEL, LLC 358      
312-239 2 Chicago Zone 01-Canal IL   460K FIRST COMMUNICATIONS, LLC 358      
312-239 3 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-239 4 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 5 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      
312-239 6 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-239 7 Chicago Zone 01-Canal IL BNSVILDGDS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-239 8 Chicago Zone 01-Canal IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-239 9 Chicago Zone 01-Canal IL CHCGILCLDS9  7421 AT&T - LOCAL 358      

Last updated: Wed, 20 Nov 2024 21:20:06 UTC

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