Local Calling Guide

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NPA: 331 [Rate centres in NPA 331] [Dial plan for NPA 331]

NXX: 631

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
331-631 A Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358      
331-631 0 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-09-10   
331-631 1 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-09-10   
331-631 2 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-09-10   
331-631 3 Downers Grove IL RVDLILBDAMD  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 358   2022-09-10   
331-631 4 Downers Grove IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2022-10-29   
331-631 5 Downers Grove IL CHCGILNEXJX  318J COMCAST IP PHONE, LLC 358   2022-10-29   
331-631 6 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2022-09-09   
331-631 7 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2022-09-09   
331-631 8 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2022-09-09   
331-631 9 Downers Grove IL CHCGILIDXDX  624H ONVOY SPECTRUM, LLC 358   2022-09-09   

Last updated: Wed, 18 Jun 2025 02:30:00 UTC

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