Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 956 [Rate centres in NPA 956] [Dial plan for NPA 956]

NXX: 477

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-477 A Laredo TX SNANTXDIRMD  903C ONVOY, LLC - TX 566      
956-477 0 Laredo TX   903C ONVOY, LLC - TX 566   2017-10-23   
956-477 1 Laredo TX   903C ONVOY, LLC - TX 566   2017-10-23   
956-477 2 Laredo TX   903C ONVOY, LLC - TX 566   2017-10-23   
956-477 3 Laredo TX   903C ONVOY, LLC - TX 566   2017-10-23   
956-477 4 Laredo TX   903C ONVOY, LLC - TX 566   2018-02-24   
956-477 5 Laredo TX   903C ONVOY, LLC - TX 566   2018-04-14   
956-477 6 Laredo TX   5562 METROPCS, INC. 566   2018-04-27   
956-477 7 Laredo TX   5562 METROPCS, INC. 566   2017-10-24   
956-477 8 Laredo TX   5562 METROPCS, INC. 566   2018-04-27   
956-477 9 Laredo TX   6506 CELLCO PARTNERSHIP DBA VERIZON WIRELESS - TX 566   2018-07-19   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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