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: 394

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-394 A Belmont MA CATNMAAKPS0  7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128      
857-394 0 Belmont MA   073H TELNYX LLC 128   2022-08-01   
857-394 1 Belmont MA   892D ONVOY, LLC - MA 128   2023-08-09   
857-394 2 Belmont MA   892D ONVOY, LLC - MA 128   2023-08-09   
857-394 3 Belmont MA   7229 MCIMETRO ACCESS TRANSMISSION SERVICES LLC 128   2022-04-04   
857-394 4 Belmont MA   892D ONVOY, LLC - MA 128   2023-08-09   
857-394 5 Belmont MA   892D ONVOY, LLC - MA 128   2023-08-09   
857-394 6 Belmont MA   892D ONVOY, LLC - MA 128   2023-08-09   
857-394 7 Belmont MA   624H ONVOY SPECTRUM, LLC 128   2022-04-05   
857-394 8 Belmont MA   624H ONVOY SPECTRUM, LLC 128   2022-04-05   
857-394 9 Belmont MA   268F PEERLESS NETWORK OF MASSACHUSETTS, LLC - MA 128   2022-06-23   

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

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