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: 473

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-473 A Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2024-12-29   
312-473 0 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2007-01-06   
312-473 1 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2007-01-06   
312-473 3 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358   2007-01-06   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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