Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: SNFCCA21XOZ

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NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
831-777 0 Santa Cruz CA 321J HD CARRIER LLC 722   2016-06-28   
831-777 1 Santa Cruz CA 321J HD CARRIER LLC 722   2016-06-28   
831-999 4 Santa Cruz CA 321J HD CARRIER LLC 722   2016-06-13   
831-999 5 Santa Cruz CA 321J HD CARRIER LLC 722   2016-06-17   
831-999 6 Santa Cruz CA 321J HD CARRIER LLC 722   2016-06-13   
925-500 6 Martinez CA 321J HD CARRIER LLC 722   2016-06-06   
925-500 7 Martinez CA 321J HD CARRIER LLC 722   2016-06-06   
925-500 9 Martinez CA 321J HD CARRIER LLC 722   2016-06-06   
925-693 2 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-693 4 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-693 5 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-693 6 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-723 5 Martinez CA 321J HD CARRIER LLC 722   2016-06-06   
925-723 6 Martinez CA 321J HD CARRIER LLC 722   2016-06-06   
925-844 0 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-844 6 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-844 8 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-957 3 Martinez CA 321J HD CARRIER LLC 722   2013-04-05   
925-993 A Clayton CA 321J HD CARRIER LLC 722      
925-993 0 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-993 3 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-993 5 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   
925-993 6 Clayton CA 321J HD CARRIER LLC 722   2016-10-20   

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Last updated: Wed, 04 Mar 2026 03:00:52 UTC

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