Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 660 [Rate centres in NPA 660] [Dial plan for NPA 660]

NXX: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
660-340 A Marshall MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2025-10-26   
660-340 6 Marshall MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2025-11-29   
660-340 7 Marshall MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2025-11-14   
660-340 8 Marshall MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2025-11-10   
660-340 9 Marshall MO   6534 NEW CINGULAR WIRELESS PCS, LLC - IL 524   2025-10-26   

Last updated: Sat, 15 Nov 2025 03:38:44 UTC

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