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: 820

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
312-820 A Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 0 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 1 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 2 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 3 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 4 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 5 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 6 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 7 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 8 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      
312-820 9 Chicago Zone 01-Calumet IL CHCGIL24DS6  224C ONVOY, LLC 358      

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

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