Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 319 [Rate centres in NPA 319] [Dial plan for NPA 319]

NXX: 340

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
319-340 A Waterloo IA CDRRIAAX7MD  6529 T-MOBILE USA, INC. 635      
319-340 0 Waterloo IA   6570 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 635   2022-09-27   
319-340 1 Waterloo IA   6570 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 635   2022-09-27   
319-340 2 Waterloo IA   508J CENTURYLINK COMMUNICATIONS, LLC 635   2023-06-11   
319-340 3 Waterloo IA   6570 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IA 635   2023-06-11   
319-340 4 Waterloo IA   221F ONVOY, LLC - IA 635   2023-05-11   
319-340 5 Waterloo IA   490J DISH WIRELESS, LLC 635   2023-06-11   
319-340 6 Waterloo IA   695G IMON COMMUNICATIONS, LLC - IA 635   2024-07-01   
319-340 7 Waterloo IA   939H COMMIO, LLC 635   2022-09-27   
319-340 8 Waterloo IA   6529 T-MOBILE USA, INC. 635   2022-09-26   
319-340 9 Waterloo IA   6529 T-MOBILE USA, INC. 635   2022-09-26   

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

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