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NPA: 312 [Rate centres in NPA 312] [Dial plan for NPA 312]

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NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-995 5 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2014-10-13   
312-995 6 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2014-10-13   
312-995 7 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2014-10-13   
312-995 8 Chicago Zone 01-Calumet IL CHCGILCGDS1  7136 TELEPORT COMMUNICATIONS AMERICA, LLC - IL 358   2014-10-13   
312-995 9 Chicago Zone 01-Calumet IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2014-10-14   
312-996 A Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 A Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 0 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 1 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 2 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 3 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 4 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 5 Chicago Zone 01-Monroe IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2014-05-03   
312-997 6 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 7 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 8 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-997 9 Chicago Zone 01-Monroe IL CHCGILMODS1  9329 ILLINOIS BELL TEL CO 358      
312-998 A Chicago Zone 01-Calumet IL CHCGILDT8MD  508J CENTURYLINK COMMUNICATIONS, LLC 358      
312-998 0 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 1 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 2 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 3 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 4 Chicago Zone 01-Calumet IL CHCGILDT8MD  508J CENTURYLINK COMMUNICATIONS, LLC 358   2014-10-03   
312-998 5 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 6 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 7 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 8 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-998 9 Chicago Zone 01-Calumet IL ELGNILOTGT5  6529 T-MOBILE USA, INC. 358   2014-10-10   
312-999 A Chicago Zone 01-Calumet IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358      
312-999 0 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 1 Chicago Zone 01-Calumet IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-12-02   
312-999 2 Chicago Zone 01-Calumet IL CHCGILGMDS7  6115 LEVEL 3 COMMUNICATIONS, LLC - IL 358   2010-12-02   
312-999 3 Chicago Zone 01-Calumet IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2024-10-14   
312-999 4 Chicago Zone 01-Calumet IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-12-02   
312-999 5 Chicago Zone 01-Calumet IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-12-02   
312-999 6 Chicago Zone 01-Calumet IL DWGVILMCPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 358   2010-12-02   
312-999 7 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 8 Chicago Zone 01-Calumet IL CHCGILWBXDZ  984E BANDWIDTH.COM CLEC, LLC - IL 358   2011-08-14   
312-999 9 Chicago Zone 01-Calumet IL CHCGILWUX6X  460K FIRST COMMUNICATIONS, LLC 358   2014-01-02   

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Last updated: Mon, 15 Sep 2025 02:24:40 UTC

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