Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 572 [Rate centres in NPA 572] [Dial plan for NPA 572]

NXX: 552

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
572-552 A Calvin OK OKCYOKCEXJY  409F ONVOY, LLC - OK 536      
572-552 0 Calvin OK   073H TELNYX LLC 536   2023-05-14   
572-552 1 Calvin OK   409F ONVOY, LLC - OK 536   2023-07-24   
572-552 5 Calvin OK   409F ONVOY, LLC - OK 536   2023-03-16   
572-552 8 Calvin OK   624H ONVOY SPECTRUM, LLC 536   2025-01-22   
572-552 9 Calvin OK   384H PEERLESS NETWORK OF OKLAHOMA, LLC - OK 536   2023-07-27   

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

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