Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
  • Effective date searches are available only for US area codes. Our sources for non-US NPA-NXX data do not provide this information.
  • If you want to search an entire area code regardless of activity, leave both the next and past days fields set to zero.

Switch: MTRYCAPM5MD

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
831-392 2 Monterey CA 145J TERRA NOVA TELECOM INC. 736   2024-11-12   
831-583 3 Monterey CA 145J TERRA NOVA TELECOM INC. 736   2024-05-10   
831-665 0 Hollister CA 145J TERRA NOVA TELECOM INC. 736   2024-02-12   
831-821 7 Tres Pinos CA 145J TERRA NOVA TELECOM INC. 736   2024-02-12   
831-887 A Monterey CA 145J TERRA NOVA TELECOM INC. 736      
831-921 0 Tres Pinos CA 145J TERRA NOVA TELECOM INC. 736   2024-12-31   

Last updated: Thu, 20 Nov 2025 13:34:34 UTC

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