Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 309 [Rate centres in NPA 309] [Dial plan for NPA 309]

NXX: 542

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-542 A McLean IL BLTNILXDXHY  624H ONVOY SPECTRUM, LLC 366   2024-02-19   
309-542 0 McLean IL   073H TELNYX LLC 366   2020-07-16   
309-542 1 McLean IL   495J STRATUS NETWORKS 366   2020-10-14   
309-542 5 McLean IL   624H ONVOY SPECTRUM, LLC 366   2023-06-02   
309-542 6 McLean IL   145J TERRA NOVA TELECOM INC. 366   2023-06-24   

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

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