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: 991

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
210-991 A San Antonio TX SNANTXCADS5  7421 AT&T - LOCAL 566      

Last updated: Sun, 07 Dec 2025 22:02:11 UTC

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