Where is 617 area code in the United States?
Area code 617 serves Boston and thirteen other communities including Belmont, Cambridge, and Chelsea in the US state of Massachusetts. It also partially serves the counties of Middlesex, Norfolk, and Suffolk. 617 is one of the first area codes assigned along with the introduction of the North American Numbering Plan (NANP) in 1947. In 2001, it was overlaid by area code 857 to cater to the growing population and phone usage in the region. Area codes 617 and 857 can be attached to both landline and cell phone numbers, as well as virtual phone numbers.