Massachusetts · Eastern Time
351 Area Code
Area code 351 is in Massachusetts, serving northeastern Massachusetts including Lowell, Lawrence, the North Shore and Fitchburg. It is in the Eastern Time zone. It shares its territory with overlay code 978, so 10-digit dialing is required.
Last updated October 1, 2026 · Source: NANPA
Where is the 351 area code?
351 is a Massachusetts area code covering northeastern Massachusetts including Lowell, Lawrence, the North Shore and Fitchburg. In the wider directory it sits in the Northeast region.
Cities in the 351 area code
- Lowell
- Lawrence
- Haverhill
- Peabody
- Methuen
- Salem
- Beverly
- Leominster
- Fitchburg
- Billerica
- Chelmsford
- Andover
- Gloucester
- Newburyport
Counties served by 351
Middlesex County, Essex County and Worcester County.
351 overlay codes and dialing
The 351 territory is covered by an overlay of 2 area codes: 351, 978. All of them serve the same geographic area, and the original code is 978. Because more than one code covers the same ground, 10-digit dialing is mandatory — you must dial the area code for every local call. New phone lines may be assigned any of these codes.
History of the 351 area code
351 went into service on May 2, 2001 as an overlay of 978, relieving number exhaustion in the Lowell area. Rather than splitting the region, the overlay lets existing customers keep their numbers while new lines draw from the added code. Learn more in our overlay guide.
Is 351 a scam or spam risk?
351 is a legitimate geographic area code, not a premium or toll line, so a call from it costs you nothing extra. That said, scammers frequently spoof real local area codes to look familiar on caller ID. A genuine 351 number on your screen is no guarantee the caller is in Lowell, MA or trustworthy. See spam & scam-risk area codes for how spoofing works and how to respond.
Other Massachusetts area codes
Explore more
See every code in Massachusetts, compare codes across the Northeast region, or view all Eastern Time codes. You can also browse the 3XX block or the complete numeric list of US area codes.
New to how this all works? Start with how area codes work, then read up on overlays, 10-digit dialing, and spam & scam-risk codes. To check another number, use the area code lookup tool.
Quick answers
351 area code FAQ
Where is the 351 area code?
The 351 area code is in Massachusetts, covering northeastern Massachusetts including Lowell, Lawrence, the North Shore and Fitchburg, in the Northeast region.
What cities are in the 351 area code?
Cities in the 351 area code include Lowell, Lawrence, Haverhill, Peabody, Methuen, Salem, Beverly, Leominster, Fitchburg and Billerica.
What time zone is 351 in?
351 is in the Eastern Time zone.
What is the overlay for the 351 area code?
351 shares its territory with 978. Both codes (351, 978) serve the same area, so 10-digit dialing is required for every call.
When did the 351 area code start?
351 went into service on May 2, 2001 as an overlay of 978.
Do I have to dial 10 digits for 351?
Yes. Because 351 is an overlay area, you must dial the full 10-digit number (area code + 7 digits) for every call.
Is 351 a toll-free or premium code?
No. 351 is a standard geographic area code, so calling it costs the same as any local or long-distance call on your plan. Toll-free calls use 800, 888, 877, 866, 855, 844 or 833.