Local Calling Guide

Area code/prefix search

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Milbank, SD

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
605-991 2   106F BANDWIDTH.COM CLEC, LLC - SD 640   2021-07-29   
605-991 3   5180 LEVEL 3 COMMUNICATIONS, LLC - SD 640   2023-01-07   
605-991 4   624H ONVOY SPECTRUM, LLC 640   2024-12-20   

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

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