Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 737 [Rate centres in NPA 737] [Dial plan for NPA 737]

NXX: 422

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
737-422 A San Marcos TX   145J TERRA NOVA TELECOM INC. 558      
737-422 2 San Marcos TX   145J TERRA NOVA TELECOM INC. 558   2025-09-09   

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

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