Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 231 [Rate centres in NPA 231] [Dial plan for NPA 231]

NXX: 278

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
231-278 A Hesperia MI MSKGMIXKQMD  624H ONVOY SPECTRUM, LLC 348      
231-278 0 Hesperia MI   792K CHARTER IP ENABLED SERVICES, LLC 348   2021-06-10   
231-278 1 Hesperia MI   543C ONVOY, LLCV - MI 348   2023-08-12   
231-278 2 Hesperia MI   624H ONVOY SPECTRUM, LLC 348   2021-06-19   
231-278 3 Hesperia MI   516J TON80 COMMUNICATIONS, LLC 348   2021-10-01   
231-278 4 Hesperia MI   543C ONVOY, LLCV - MI 348   2022-12-29   
231-278 5 Hesperia MI   543C ONVOY, LLCV - MI 348   2023-04-28   
231-278 6 Hesperia MI   543C ONVOY, LLCV - MI 348   2023-10-08   
231-278 7 Hesperia MI   543C ONVOY, LLCV - MI 348   2020-12-26   
231-278 8 Hesperia MI   543C ONVOY, LLCV - MI 348   2020-12-26   
231-278 9 Hesperia MI   624H ONVOY SPECTRUM, LLC 348   2021-12-20   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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