Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 657 [Rate centres in NPA 657] [Dial plan for NPA 657]

NXX: 271

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
657-271 A Westminster CA TRNECAGBGT3  6529 T-MOBILE USA, INC. 730      
657-271 0 Westminster CA   829J PAETEC ITEL, LLC 730   2015-07-21   
657-271 1 Westminster CA   515J IP HORIZON LLC 730   2015-09-19   
657-271 2 Westminster CA   649C ONVOY, LLC - CA 730   2015-08-17   
657-271 3 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-09-17   
657-271 4 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-09-17   
657-271 5 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-07-04   
657-271 6 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-07-04   
657-271 7 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-07-04   
657-271 8 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-07-04   
657-271 9 Westminster CA   6529 T-MOBILE USA, INC. 730   2015-07-04   

Last updated: Thu, 29 Jan 2026 14:35:03 UTC

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