Haverhill, Massachusetts

Where Is Area Code 351?

Area code 351 is in northeastern Massachusetts. It serves the same region as area code 978 because 351 is an overlay code. This area includes parts of the Merrimack Valley and North Shore, and it reaches north to the New Hampshire state line.

Area code 351 covers Haverhill, Lowell, Lawrence, Fitchburg, and many nearby communities. It also serves parts of Essex County and Middlesex County. In common use, 351 appears across the same calling area as 978.

This region includes the Merrimack River, which runs through cities such as Lowell, Lawrence, and Haverhill. Notable places in the broader 351 and 978 service area include Lowell National Historical Park in Lowell and the industrial mill districts that shaped the Merrimack Valley.

History of Area Code 351

Area code 351 was created as an overlay to area code 978. The Massachusetts Department of Telecommunications and Cable approved the overlay in 2000, and area code 351 entered service on May 2, 2001. Before that change, the region used only area code 978.

Area code 978 itself had been split from area code 508 in 1997. The overlay happened because the region needed more phone numbers as demand grew for cell phones, fax lines, and other services. Since 351 is an overlay, it did not replace 978, and both area codes still serve the same territory.

Key Facts About Area Code 351

• Area code 351 is a Massachusetts area code, and Haverhill is one of the cities in its service area.
• Area code 351 is an overlay of area code 978, and both codes serve the same geographic region.
• Area code 351 officially entered service on May 2, 2001.
• The 351 and 978 area serves northeastern Massachusetts, including cities such as Lowell, Lawrence, Fitchburg, and Haverhill.
• Area code 351 is in the Eastern Time Zone.
• Area code 351 covers parts of Essex County and Middlesex County in Massachusetts.
• The service area includes major regional landmarks such as the Merrimack River and Lowell National Historical Park.
• Ten-digit dialing is required in the 351 and 978 overlay area because two area codes serve the same region.

Frequently Asked Questions

What state is area code 351 in?

Area code 351 is in Massachusetts.

What major cities use area code 351?

Major cities in area code 351 include Haverhill, Lowell, Lawrence, and Fitchburg.

Is area code 351 a toll-free number?

No. Area code 351 is a geographic area code.