Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

NPA: 307 [Rate centres in NPA 307] [Dial plan for NPA 307]

NXX: 407

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-407 A West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640      
307-407 0 West Spearfish WY SXFLSDCORMD  9416 LEVEL 3 COMMUNICATIONS, LLC - WY 640   2023-01-27   
307-407 1 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2021-07-11   
307-407 2 West Spearfish WY SXFLSDCOX0X  624H ONVOY SPECTRUM, LLC 640   2022-01-08   
307-407 3 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2020-10-10   
307-407 4 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2020-10-10   
307-407 5 West Spearfish WY SXFLSDCOX0X  624H ONVOY SPECTRUM, LLC 640   2021-07-18   
307-407 6 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2021-03-02   
307-407 7 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2021-03-02   
307-407 8 West Spearfish WY SXFLSDCOTMD  450F ONVOY, LLC - WY 640   2021-08-27   
307-407 9 West Spearfish WY SXFLSDCOX0X  624H ONVOY SPECTRUM, LLC 640   2021-10-30   

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

Sponsored by: VoIP Much Phone Company

Like this site? We accept donations via PayPal.