The area code 617 is located in Boston, Massachusetts.
Area code 617 serves the heart of Boston, Massachusetts, and nearby inner suburbs in the Greater Boston area. Introduced in 1947 as one of the original North American Numbering Plan codes, it remains closely tied to Boston’s identity and history. The 617 region uses an overlay with area code 857 (added in 2001), so ten-digit dialing is required. The area observes Eastern Time (ET), including daylight saving time.
The 617 area code covers Boston’s core neighborhoods and several well-known communities just outside the city. It includes major landmarks like Fenway Park, Boston Common, the Freedom Trail, Logan International Airport, and world-class universities such as Harvard University and MIT in Cambridge. Key cities and towns in 617 include:
“Established in 1947; overlay 857 introduced in 2001.” — North American Numbering Plan Administration (NANPA)
Area code 617 has changed over time as the region grew. It once covered a larger part of eastern Massachusetts before splits created 508 (1988) and 781 (1997), leaving 617 focused on Boston and its closest suburbs. Today, 617 numbers appear on both mobile phones and landlines, and number portability means a phone number can often stay with you when you move within the area. When you see a 617 phone number, it usually points to the Boston metro—home to historic sites, innovation hubs like Kendall Square, and a vibrant mix of neighborhoods.