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: 990

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
857-990 A Boston MA BSTPMALLMMD  139F WORLDCALL INTERCONNECT INC. 128      
857-990 0 Boston MA   139F WORLDCALL INTERCONNECT INC. 128   2015-11-13   
857-990 1 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2016-01-10   
857-990 2 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2016-01-10   
857-990 3 Boston MA   318J COMCAST IP PHONE, LLC 128   2015-11-17   
857-990 4 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2015-12-13   
857-990 5 Boston MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128   2015-12-13   
857-990 6 Boston MA   990E BANDWIDTH.COM CLEC, LLC - MA 128   2016-01-10   
857-990 7 Boston MA   321J HD CARRIER LLC 128   2016-02-19   
857-990 8 Boston MA   5562 METROPCS, INC. 128   2016-06-19   
857-990 9 Boston MA   892D ONVOY, LLC - MA 128   2016-01-11   

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

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