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: 521

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-521 A Chicago Zone 01-Calumet IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-521 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358      
312-521 1 Chicago Zone 01-Calumet IL CHCGILWUDS4  063E PEERLESS NETWORK OF ILLINOIS, LLC - IL 358      
312-521 2 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358      
312-521 3 Chicago Zone 01-Calumet IL CHCGILMF4MD  5562 METROPCS, INC. 358      
312-521 4 Chicago Zone 01-Calumet IL   829J PAETEC ITEL, LLC 358      
312-521 5 Chicago Zone 01-Calumet IL CHCGILDTDS3  5447 ACCESS ONE, INC. - IL 358      
312-521 6 Chicago Zone 01-Calumet IL   7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358      
312-521 7 Chicago Zone 01-Calumet IL   460K FIRST COMMUNICATIONS, LLC 358      
312-521 8 Chicago Zone 01-Calumet IL   829J PAETEC ITEL, LLC 358      
312-521 9 Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358      

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

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