Local Calling Guide

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NPA: 810 [Rate centres in NPA 810] [Dial plan for NPA 810]

NXX: 320

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-320 A Port Huron MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-320 0 Port Huron MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-320 1 Port Huron MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-320 2 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-06-18   
810-320 3 Port Huron MI FLNTMICD0MD  829J PAETEC ITEL, LLC 340   2007-09-13   
810-320 4 Port Huron MI   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 340   2025-05-23   
810-320 5 Port Huron MI   6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 340   2025-05-27   
810-320 6 Port Huron MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-320 7 Port Huron MI SFLDMIDNDS6  6120 LEVEL 3 COMMUNICATIONS, LLC - MI 340      
810-320 8 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-06-18   
810-320 9 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-06-18   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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