What is what area code is 857?

The area code 857 is a North American Numbering Plan area code that covers the city of Boston and several of its surrounding suburbs in Massachusetts. It was established as an overlay to the existing 617 area code in 2001 to ensure that there were enough phone numbers available for new customers in the region.

The 857 area code serves locations such as Allston, Brighton, Charlestown, Chelsea, Dorchester, and Roxbury in Boston, as well as parts of Brookline, Cambridge, Quincy, and Somerville. It is one of the many area codes that cover the Greater Boston area.

If you have a phone number with a 857 area code, it means that your phone is registered in one of these cities or towns in Massachusetts.