Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 447 [Rate centres in NPA 447] [Dial plan for NPA 447]

NXX: 257

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
447-257 A Mason City IL SPFDILES7MD  224C ONVOY, LLC 374      
447-257 0 Mason City IL SPFDILESXYX  495J STRATUS NETWORKS 374   2021-12-13   
447-257 1 Mason City IL SPFDILMBWMD  073H TELNYX LLC 374   2023-11-16   
447-257 2 Mason City IL SPFDILESXWX  6333 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - IL 374   2024-09-01   
447-257 4 Mason City IL SPFDILES7MD  224C ONVOY, LLC 374   2021-06-25   
447-257 7 Mason City IL SPFDILES7MD  224C ONVOY, LLC 374   2021-08-01   
447-257 8 Mason City IL SPFDILESXQX  624H ONVOY SPECTRUM, LLC 374   2024-05-24   
447-257 9 Mason City IL SPFDILESX8Y  490J DISH WIRELESS, LLC 374   2023-11-13   

Last updated: Sun, 26 Jan 2025 15:59:20 UTC

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