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: 400

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
309-400 A Rock Island IL DVNPIADTX5Y  516C AT&T CORP. 634   2024-12-10   
309-400 0 Rock Island IL   145J TERRA NOVA TELECOM INC. 634   2025-05-28   
309-400 1 Rock Island IL   6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 634   2025-08-19   
309-400 7 Rock Island IL DVNPIADTX5Y  516C AT&T CORP. 634   2024-12-10   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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