857 Area Code
Covers Boston and nearby communities in Massachusetts.
(857) 555-0142Area code 857 map
Interactive coverage map for area code 857, centered on Boston, Massachusetts
42.3751, -71.1056
Open in OpenStreetMapArea code 857 coverage map — centered on Boston. Shaded area shows the approximate reach around the primary city.
Calls tagged with area code 857 come from Boston and nearby communities in Massachusetts. It reaches roughly 1.1 million people across places such as Boston, Cambridge, Quincy, Newton and more. The region observes Eastern time, so a number like (857) 555-0142 is on that clock right now. On the ground it spans Suffolk, Middlesex, Norfolk. It shares its territory with the overlay code 617, which sit on the exact same map. Because the 857 region uses more than one area code, you must dial all ten digits — area code included — even for a local call. You do not, however, need to dial a leading 1 for calls within the US and Canada. Scroll on for a real-time clock, an area map, the cities and counties inside 857, its related area codes, and practical advice on 857 robocalls and caller-ID spoofing.
Cities covered by 857
Cities & neighborhoods
- Boston
- Cambridge
- Quincy
- Newton
- Somerville
- Everett
- Chelsea
- Belmont
- Brookline
- Milton
- South Boston
- Watertown
Nearby & overlay area codes
Overlay codes (same area)
These share 857’s geography — a number in either code can be on the same street.
Neighboring codes
Codes for adjacent regions and metros.
Is a call from 857 a scam?
Because 857 covers a dense metro around Boston, it's a common source of both real business calls and spam. Legitimate 857 calls come from local businesses, offices and neighbors; scam calls in this region tend to imitate delivery services, banks and utilities. Remember that caller ID is trivially spoofed — a scammer anywhere can make a 857 number appear on your screen — so the area code alone never proves a call is genuinely local.
Red flags to watch for
- Pressure to act right now, or threats of arrest, fines, or service being cut off.
- Requests to pay with gift cards, wire transfer, crypto, or a payment app.
- Asking for passwords, one-time codes, your SSN, or full card/bank numbers.
- A robocall or recording, or a number that won’t let you call back.
When unsure, hang up and call the organization back on a number you look up yourself.
Calling a 857 number from abroad
Every 857 number is a US/Canada +1 number. From a mobile anywhere, the simplest approach is to dial it in international format:
+1 857 555-0142If your phone can’t dial the +, replace it with your country’s exit code, then 1, then the number:
- UK, Germany, France & most of Europe
00 1 857 555-0142 - Australia
0011 1 857 555-0142 - Japan
010 1 857 555-0142 - Mexico
00 1 857 555-0142
Within the US and Canada you don’t need any of this — just dial the ten digits 857 555-0142.
Reverse phone lookup
Check any US or Canada number to see whether it's a working line, which carrier it sits on, whether it's mobile, landline or VoIP, and roughly where it's registered.
Shows carrier, line type and location. Owner name isn't available here.
Results are for personal, informational use only and may not be used for employment, credit, housing or tenant-screening decisions.
Area code 857: frequently asked questions
Where is the 857 area code located?
The 857 area code is located in Massachusetts, centered on Boston. It covers Suffolk, Middlesex, Norfolk and nearby communities including Boston, Cambridge, Quincy, Newton, Somerville, Everett.
What time zone is 857 in?
Area code 857 is in the Eastern time zone (UTC-5 (EST) / UTC-4 (EDT)). You can see the exact current local time for Boston on the live clock above.
What cities use area code 857?
Cities and areas that use 857 include Boston, Cambridge, Quincy, Newton, Somerville, Everett. Its primary city is Boston, MA.
Do I need to dial 1 before 857?
For calls within the US, you do not need to dial a leading 1, but you do need all ten digits: 857 plus the seven-digit number. The 857 area requires ten-digit dialing because more than one area code serves it.
Is 857 a toll-free or scam number?
No — 857 is a normal geographic area code for Boston, not a toll-free code (toll-free codes are 800, 833, 844, 855, 866, 877 and 888). A 857 number is not inherently a scam, but the code can be spoofed. See the spam-call section above for how to tell.
What are the overlay area codes for 857?
Area code 857 is overlaid by 617, meaning those codes cover the same geographic area.