Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 857 [Rate centres in NPA 857] [Dial plan for NPA 857]

NXX: 335

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-335 A Boston MA BSTPMALLX0X  425J CSC WIRELESS, LLC 128      
857-335 0 Boston MA   5562 METROPCS, INC. 128   2020-06-06   
857-335 1 Boston MA   892D ONVOY, LLC - MA 128   2020-06-15   
857-335 2 Boston MA   425J CSC WIRELESS, LLC 128   2019-07-28   
857-335 3 Boston MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2019-08-05   
857-335 4 Boston MA   892D ONVOY, LLC - MA 128   2023-06-26   
857-335 5 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2019-10-03   
857-335 6 Boston MA   5562 METROPCS, INC. 128   2020-06-06   
857-335 7 Boston MA   4036 NEW CINGULAR WIRELESS PCS, LLC - DC 128   2019-10-12   
857-335 8 Boston MA   892D ONVOY, LLC - MA 128   2020-06-15   
857-335 9 Boston MA   892D ONVOY, LLC - MA 128   2020-06-15   

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

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