Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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Switch: CSRKAZXCRS1

NPA-NXX BLOCK Rate Centre Region OCN LATA LIR Eff date Disc date
928-764 A Castle Rock AZ 2172 CITIZENS UTILITIES RURAL DBA FRONTIER UT RURAL 666      

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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