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: 440

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-440 A Harlingen TX HRLNTXHGDS0  9533 SOUTHWESTERN BELL 568      
956-440 0 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 1 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 2 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 3 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 4 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 5 Harlingen TX   5562 METROPCS, INC. 568   2019-02-25   
956-440 6 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 7 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 8 Harlingen TX   9533 SOUTHWESTERN BELL 568      
956-440 9 Harlingen TX   9533 SOUTHWESTERN BELL 568      

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

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