Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 580 [Rate centres in NPA 580] [Dial plan for NPA 580]

NXX: 635

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
580-635 A Hillsdale OK HLDLOKMARL0  9533 SOUTHWESTERN BELL 536      
580-635 0 Hillsdale OK OKCYOKCEXJZ  624H ONVOY SPECTRUM, LLC 536   2025-01-22   
580-635 1 Hillsdale OK HLDLOKMARL0  9533 SOUTHWESTERN BELL 536      
580-635 2 Hillsdale OK HLDLOKMARL0  9533 SOUTHWESTERN BELL 536      
580-635 3 Hillsdale OK OKCZOKZCFMD  5257 LEVEL 3 COMMUNICATIONS, LLC - OK 536   2019-06-28   

Last updated: Sun, 01 Jun 2025 02:18:11 UTC

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