Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 210 [Rate centres in NPA 210] [Dial plan for NPA 210]

NXX: 637

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
210-637 A San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 0 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 1 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 2 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 3 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 4 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 5 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 6 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 7 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 8 San Antonio TX SNANTXFRDS0  9533 SOUTHWESTERN BELL 566      
210-637 9 San Antonio TX   793K TWC IP ENABLED SERVICES, LLC 566   2007-09-24   

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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