Local Calling Guide

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NPA: 909 [Rate centres in NPA 909] [Dial plan for NPA 909]

NXX: 551

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
909-551 A Diamond Bar CA   793K TWC IP ENABLED SERVICES, LLC 730      
909-551 0 Diamond Bar CA   793K TWC IP ENABLED SERVICES, LLC 730   2014-12-15   
909-551 1 Diamond Bar CA RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2014-12-16   
909-551 2 Diamond Bar CA COVNCAXFX3Y  649C ONVOY, LLC - CA 730   2014-12-23   
909-551 3 Diamond Bar CA COVNCAXFX3Y  649C ONVOY, LLC - CA 730   2014-12-23   
909-551 4 Diamond Bar CA COVNCAXFX3Y  649C ONVOY, LLC - CA 730   2014-12-23   
909-551 5 Diamond Bar CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2015-05-15   
909-551 6 Diamond Bar CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2015-05-15   
909-551 7 Diamond Bar CA   829J PAETEC ITEL, LLC 730   2015-01-02   
909-551 8 Diamond Bar CA RVSDCALBCM4  6010 NEW CINGULAR WIRELESS PCS, LLC 730   2015-06-30   
909-551 9 Diamond Bar CA RVSDCAYAGT1  6529 T-MOBILE USA, INC. 730   2015-03-06   

Last updated: Tue, 16 Jun 2026 00:09:45 UTC

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