Watertown, Massachusetts Area Code

Watertown, MA is officially utilizing an area code overlay in which area codes 617 and 857 serve the same geographic area. Ten digit dialing (area code + seven digit number) is necessary.

In addition to Watertown, MA area code information read more about area codes 617 and 857 details and Massachusetts area codes.

Watertown, MA is located in Middlesex County and observes the Eastern Time Zone. View our Times by Area Code tool.