The 781 area code covers Waltham, Lexington and 38 more places in Massachusetts.
Area code 781 is in Massachusetts, on Eastern Time. In the 781 area, phone numbers are given out most in Middlesex County, then Norfolk and Plymouth counties. It has been in service since September 1, 1997. 339 covers the same area, so two neighbours can have different area codes.
- Where
- 5 counties in Massachusetts, mostly Middlesex County, Norfolk County and Plymouth County
- Time zone
- Eastern Time
- In service since
- September 1, 1997
- Shares its area with
- 339 (since 2001)
- Prefixes in use
- 769
- How to dial
- Local calls need all 10 digits: 781-555-0142.
Find out who called you from a 781 number.
Enter the full 10-digit number to see who it is listed to and the city and state on the listing. It is the same free check as our who called me lookup. To see only the caller ID name on the number, use our free CNAM lookup. To see whether it is a mobile, a landline or a VoIP line, use our free VoIP checker. To see which carrier a (781) number is on today, use our free carrier lookup.
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Waltham holds 9% of the phone prefixes in area code 781.
A prefix is the three digits after the area code, and NANPA assigns each one to a town. Counting the 769 prefixes in use shows where 781 numbers are actually given out.
- Waltham72 prefixes, 9%
- Lexington56 prefixes, 7%
- Burlington41 prefixes, 5%
- Lynn38 prefixes, 5%
- Woburn38 prefixes, 5%
- Dedham35 prefixes, 5%
- Needham33 prefixes, 4%
- Braintree31 prefixes, 4%
Also served: Medford, Canton, Norwood and Weymouth and 28 smaller places.
Of the carriers named here, PAETEC (Windstream) holds the most phone number prefixes in area code 781: 69 of 769.
NANPA, which runs the North American numbering plan, assigns each prefix (the three digits after the area code) to one carrier. Here is how the 769 prefixes in use in 781 divide between carriers; holders this page does not name are grouped as other carriers.
| Carrier | Prefixes | Share |
|---|---|---|
| PAETEC (Windstream)Windstream's business phone network | 69 | 9% |
| Level 3 (Lumen)Lumen's business and wholesale network | 59 | 8% |
| TC Systems | 57 | 7% |
| Metro by T-MobileT-Mobile's prepaid brand | 43 | 6% |
| Comcast (Xfinity)Cable company's phone service | 35 | 5% |
| BandwidthSupplies numbers to VoIP and app-based phone services | 34 | 4% |
| 20 other carriers | 472 | 61% |
78% of these prefixes are pooled, which means the blocks of 1,000 numbers inside them can belong to other carriers. Any number can also have been moved to another carrier since, so this shows who holds the prefixes, not who serves a given number.
Want the carrier of one exact number? Our free carrier lookup checks it, because numbers move between carriers.
Source: NANPA central office code assignments, October 1, 2026.
781 has been overlaid once since 1997.
1997
781 starts on September 1, 1997, split off from 617.
2001
On May 2, 2001, 339 is added on top of 781, so new numbers here can get either code.
A 781 number on your screen can still be a scam, because caller ID is easy to fake.
- Let an unknown call go to voicemail. A real caller leaves a message; a robocaller usually does not.
- Look the number up with the box above before you call back, because calling back tells a robocaller your line is live.
- Hang up on anyone who wants gift cards, crypto or a wire transfer, or asks you to read out a code that was just texted to you.
- Report unwanted robocalls at reportfraud.ftc.gov, or paste a suspicious message into our free scam checker.
The area codes closest to 781 are 617, 508 and 978.
This list measures the distance between the centres of each area, across state lines, and shows codes that share one area together.
Massachusetts has 8 other area codes.
These are the questions people ask most about area code 781.
Where is area code 781?
781 covers Waltham, Lexington, Burlington and Lynn and 36 more places in Massachusetts. In the 781 area, phone numbers are given out most in Middlesex County, then Norfolk and Plymouth counties.
What state is area code 781 in?
Massachusetts. 781 is a Massachusetts area code on Eastern Time.
What cities use area code 781?
The places holding the most 781 prefixes are Waltham, Lexington, Burlington, Lynn, Woburn, Dedham, Needham and Braintree, out of 40 places in all. The count comes from NANPA's prefix assignments as of October 1, 2026.
Which phone company owns area code 781?
No single phone company owns 781. NANPA's records list its 769 prefixes across many carriers, and the ones named on this page include PAETEC (Windstream), Level 3 (Lumen) and TC Systems. Numbers move between carriers, so check one exact number with a carrier lookup.
What time zone is area code 781 in?
781 is on Eastern Time.
When did area code 781 start?
781 went into service on September 1, 1997, when it was split off from 617.
Is 781 the same area as 339?
Yes. 339 (since 2001) covers the same ground as 781. Nobody's number changed when it was added; new lines simply get whichever code has numbers left, so two neighbours can have different codes.
How do I dial a 781 number?
Local calls need all 10 digits: 781-555-0142.
Is 781 a toll-free number?
No. 781 is a regular area code for Waltham and Lexington in Massachusetts, not a toll-free one. The toll-free codes in North America are 800, 833, 844, 855, 866, 877 and 888.
What area codes are near 781?
The closest are 617/857 (Boston, Massachusetts), 508/774 (Worcester, Massachusetts), 978/351 (Lowell, Massachusetts) and 401 (Providence, Rhode Island), measured between the centres of each area.
Who called me from a 781 number?
Enter the full 10-digit number in the lookup above. It returns the listed owner where there is a public record, where the number is registered, and whether it is a mobile, a landline or a VoIP line.
Is area code 781 a scam?
781 is a real Massachusetts area code, so the code itself is not a warning sign. Scam callers fake local-looking numbers on purpose, so judge the call by what the caller asks for, and look the number up before calling back.
Put this lookup on your site: our free area code widget takes two lines of code and shows any US area code's state, time zone and local time.
Source: NANPA, the North American Numbering Plan Administrator: its area code database and prefix assignments, as of October 1, 2026.