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: 971

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-971 A Monmouth IL   732J NUSO, LLC 977   2025-05-26   
309-971 1 Monmouth IL   732J NUSO, LLC 977   2025-05-26   

Last updated: Sun, 27 Apr 2025 12:48:38 UTC

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