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: 951

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-951 A Washington IL   224C ONVOY, LLC 368   2026-10-22   
309-951 0 Washington IL   224C ONVOY, LLC 368   2026-10-22   

Last updated: Tue, 01 Sep 2026 00:40:05 UTC

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