Local Calling Guide

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

NXX: 233

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
956-233 A Los Fresnos TX LSFRTXLFRS0  9533 SOUTHWESTERN BELL 568      
956-233 0 Los Fresnos TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 568   2007-03-05   
956-233 1 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 2 Los Fresnos TX   793K TWC IP ENABLED SERVICES, LLC 568   2007-06-13   
956-233 3 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 4 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 5 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 6 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 7 Los Fresnos TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 568   2007-01-12   
956-233 8 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      
956-233 9 Los Fresnos TX   9533 SOUTHWESTERN BELL 568      

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

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