Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 617 [Rate centres in NPA 617] [Dial plan for NPA 617]

NXX: 604

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-604 A Hyde Park MA HYPKMAHARP0  9102 VERIZON NEW ENGLAND INC. 128      
617-604 0 Hyde Park MA   9102 VERIZON NEW ENGLAND INC. 128      
617-604 1 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-06-13   
617-604 2 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-03-06   
617-604 3 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-03-06   
617-604 4 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-06-13   
617-604 5 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-06-13   
617-604 6 Hyde Park MA   892D ONVOY, LLC - MA 128   2021-06-13   
617-604 7 Hyde Park MA   9102 VERIZON NEW ENGLAND INC. 128      
617-604 8 Hyde Park MA   9102 VERIZON NEW ENGLAND INC. 128      
617-604 9 Hyde Park MA   145J TERRA NOVA TELECOM INC. 128   2021-09-28   

Last updated: Thu, 01 Jan 2026 03:59:49 UTC

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