Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 512 [Rate centres in NPA 512] [Dial plan for NPA 512]

NXX: 551

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
512-551 A Austin TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 558      
512-551 0 Austin TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 558   2009-07-03   
512-551 1 Austin TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 558   2009-07-03   
512-551 2 Austin TX   516C AT&T CORP. 558   2009-11-13   
512-551 3 Austin TX   516C AT&T CORP. 558   2009-04-24   
512-551 4 Austin TX   6114 LEVEL 3 COMMUNICATIONS, LLC - TX 558   2008-12-27   
512-551 5 Austin TX   7516 LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 558   2009-04-16   
512-551 6 Austin TX   7516 LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 558   2009-04-16   
512-551 7 Austin TX   7516 LEVEL 3 OF TELECOM OF TEXAS, LLC - TX 558   2009-04-16   
512-551 8 Austin TX   516C AT&T CORP. 558   2009-07-03   
512-551 9 Austin TX   516C AT&T CORP. 558   2009-07-03   

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

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