Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 575 [Rate centres in NPA 575] [Dial plan for NPA 575]

NXX: 255

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
575-255 A San Ysidro NM ALBQNMMAX4Y  206F ONVOY, LLC - NM 664      
575-255 0 San Ysidro NM   206F ONVOY, LLC - NM 664   2017-10-01   
575-255 1 San Ysidro NM   206F ONVOY, LLC - NM 664   2020-10-19   
575-255 2 San Ysidro NM   206F ONVOY, LLC - NM 664   2020-01-10   
575-255 3 San Ysidro NM   206F ONVOY, LLC - NM 664   2020-10-19   
575-255 4 San Ysidro NM   206F ONVOY, LLC - NM 664   2020-08-31   
575-255 5 San Ysidro NM   206F ONVOY, LLC - NM 664   2019-10-31   
575-255 6 San Ysidro NM   206F ONVOY, LLC - NM 664   2020-08-31   
575-255 7 San Ysidro NM   5470 LEVEL 3 COMMUNICATIONS, LLC - NM 664   2017-10-26   
575-255 8 San Ysidro NM   624H ONVOY SPECTRUM, LLC 664   2025-01-22   
575-255 9 San Ysidro NM   206F ONVOY, LLC - NM 664   2021-03-04   

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

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