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: 355

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
307-355 A La Grange WY GDISNENWX2X  6529 T-MOBILE USA, INC. 646      
307-355 0 La Grange WY   450F ONVOY, LLC - WY 646   2023-06-18   
307-355 1 La Grange WY   450F ONVOY, LLC - WY 646   2021-07-11   
307-355 2 La Grange WY   450F ONVOY, LLC - WY 646   2021-04-21   
307-355 3 La Grange WY   450F ONVOY, LLC - WY 646   2021-03-01   
307-355 4 La Grange WY   450F ONVOY, LLC - WY 646   2024-01-08   
307-355 5 La Grange WY   6529 T-MOBILE USA, INC. 646   2024-04-09   
307-355 6 La Grange WY   6529 T-MOBILE USA, INC. 646   2024-07-20   
307-355 7 La Grange WY   9416 LEVEL 3 COMMUNICATIONS, LLC - WY 646   2023-01-27   
307-355 8 La Grange WY   450F ONVOY, LLC - WY 646   2023-10-12   
307-355 9 La Grange WY   6529 T-MOBILE USA, INC. 646   2020-09-28   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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