Local Calling Guide

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

NXX: 204

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
810-204 A Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340      
810-204 0 Port Huron MI DTRTMIDJCMD  6003 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - MI 340   2021-11-04   
810-204 1 Port Huron MI LIVNMIUX8MD  2964 OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC 340   2021-11-11   
810-204 2 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-03-01   
810-204 3 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-03-01   
810-204 4 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2020-12-19   
810-204 5 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2020-12-19   
810-204 6 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-03-01   
810-204 7 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-03-01   
810-204 8 Port Huron MI DTRTMIVWDMD  624H ONVOY SPECTRUM, LLC 340   2021-06-15   
810-204 9 Port Huron MI SFLDMITODS2  543C ONVOY, LLCV - MI 340   2021-06-18   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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