Area code 857 – Massachusetts
857 has served Massachusetts since 2001, split from 617. 361 of its 786 number blocks are allocated (46%). No carrier dominates: Verizon 25.8%, Other CLEC / VoIP 20.2%, T-Mobile 16.6%. It shares its geography with overlay codes 617, so local calls take all ten digits. 827 FTC complaints named a 857 caller ID in the 33 days to 30 October 2026, putting it 91st of 422 codes with five or more complaints.
- State
- Massachusetts
- In service since
- 2001
- Time zone
- Eastern
- Shares area with
- 617
Who holds 857 number blocks
Share of the 361 assigned NXX blocks (45.9% of the 786 possible), across 41 carriers. This is share of number blocks, not of subscribers.
- Verizon25.8%
- T-Mobile23.5%
- Other CLEC / VoIP12.7%
- Onvoy11.6%
- AT&T6.1%
- Windstream5.3%
- Lumen3.6%
- Bandwidth2.8%
- Comcast2.5%
- Peerless1.9%
- Charter1.9%
- TPx1.1%
- VoIP Innovations0.3%
- Vonage0.3%
- Twilio0.3%
- 8x80.3%
Spam complaints naming 857
FTC Do Not Call complaints where the caller ID was a 857 number, 28 Sep – 30 Oct 2026 (33 days). Caller IDs on spam calls are frequently spoofed, so these are complaints about the code, not calls proven to originate in it.
Rate centers in 857
NANPA allocates number blocks to rate centers and records their names abbreviated to ten characters, so these are NANPA's codes rather than place names – CHAMPAURBN is Champaign-Urbana, NWYRCYZN01 is a New York City zone. We show them unchanged instead of guessing at the full names. Showing the largest 5 of 21.
Timeline
- 2001 857 goes into service, split from or overlaid on 617.
More about 857
Separate pages for the questions that need their own answer: what time it is there, what the complaint data says, who holds the number blocks, and how the code compares with the one it shares its area with.
Frequently asked about 857
What state is area code 857?
Massachusetts. It covers the same area as 617/857.
Is a call from 857 a scam?
Not by itself. 857 drew 827 FTC complaints in the 33 days to 30 October 2026, 91st of 422 ranked codes – mid-pack or lower. Spam callers spoof caller IDs, so the only useful check is the full number.
Which carrier owns 857 numbers?
Verizon holds the largest share of assigned number blocks at 25.8%. The rest is spread across 3 other carriers. This is share of number blocks, not of subscribers – people keep their numbers when they switch carriers.
Do I need to dial 10 digits in 857?
Yes – ten digits for local calls in 857, because it shares its area with another code.
Sources and verification
- NANPA – NPA Database (npa_report.csv), file date 11/01/2026, retrieved Nov 1, 2026
- NANPA – CO Code Assignment Records, All States (utilized), file updated 11/01/2026, retrieved Nov 1, 2026
- FTC – Do Not Call Reported Calls Data, 25 daily files 28 Sep – 30 Oct 2026, retrieved Nov 1, 2026
NANPA dialing note for this code: “10D”. Reviewed by the data desk. Spotted an error? Request a correction.