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: SNRTCAHFDS0

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NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
925-464 5 Walnut Creek CA 433E SONIC TELECOM, LLC - CA 722   2012-12-27   
925-578 0 East Contra Costa CA 433E SONIC TELECOM, LLC - CA 722   2021-07-11   
925-594 4 Danville CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   
925-626 6 East Contra Costa CA 433E SONIC TELECOM, LLC - CA 722   2015-04-09   
925-635 6 Pittsburg CA 433E SONIC TELECOM, LLC - CA 722   2015-04-09   
925-723 7 Martinez CA 433E SONIC TELECOM, LLC - CA 722   2012-12-22   
925-794 3 Moraga CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   
925-800 4 Livermore CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   
925-889 8 Clayton CA 433E SONIC TELECOM, LLC - CA 722   2015-04-09   
925-913 3 Bishop Ranch CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   
925-918 9 Pleasanton CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   
925-999 3 Dublin-San Ramon CA 433E SONIC TELECOM, LLC - CA 722   2015-12-12   

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Last updated: Thu, 16 Jul 2026 02:21:55 UTC

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