Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 307 [Rate centres in NPA 307] [Dial plan for NPA 307]

NXX: 643

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-643 A West Spearfish WY SPRFSDCORS1  9631 QWEST CORPORATION 640      

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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