Local Calling Guide

Area code/prefix search

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Castroville, CA

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NPA-NXX BLOCK Switch OCN LATA LIR Eff date Disc date
831-741 5 SLNSCA01XCY  624H ONVOY SPECTRUM, LLC 736   2024-01-05   
831-741 6 SLNSCABIXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 736   2008-03-15   
831-741 7 SLNSCA01X7Y  508J CENTURYLINK COMMUNICATIONS, LLC 736   2015-11-09   
831-741 8 SLNSCABIXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 736   2021-06-06   
831-741 9 SLNSCABIXMD  6010 NEW CINGULAR WIRELESS PCS, LLC 736   2018-11-10   

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Last updated: Thu, 05 Feb 2026 23:41:55 UTC

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