Local Calling Guide

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

NXX: 273

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
617-273 A Milton MA CMBRMAORDSG  4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 0 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 1 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 2 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 3 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 4 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 6 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 7 Milton MA   624H ONVOY SPECTRUM, LLC 128   2021-11-11   
617-273 8 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      
617-273 9 Milton MA   4018 LEVEL 3 COMMUNICATIONS, LLC - MA 128      

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

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