617 Area Code: Boston, Massachusetts Location and Time Zone

Introduction

The 617 area code is Boston's code. It covers the city and a ring of close-in neighbors that includes Cambridge, Somerville, Brookline, Newton and Quincy. It's also one of the original area codes from 1947, and since May 2, 2001 it has shared its map with the overlay code 857.

617 once reached across a much larger part of eastern Massachusetts, so its current size can surprise people. This guide explains how the territory shrank, which communities still use it, how local dialing works alongside 857, and what to do when an unfamiliar 617 number calls.

Where Is the 617 Area Code?

Area code 617 is in eastern Massachusetts, centered on Boston. It covers the city itself plus the inner suburbs closest to it, a compact, densely built area rather than a broad region.

The Boston area code wasn't always this small. NANPA lists 617 in service since January 1947, when it was one of the area codes in the first nationwide plan. In 1988 the outer part of its territory became 508, and in 1997 another ring of communities moved to 781, leaving 617 with Boston and its nearest neighbors.

Some people search for area code 617 in California. There isn't one: an area code maps to a single numbering plan area, and 617's is in Massachusetts. A 617 caller may still be anywhere, since caller ID shows where a number was assigned, not where the phone is.

Cities and Counties in the 617 Area Code

617 reaches into parts of three counties. The table sorts some of its best-known communities by county; it's not a complete list, and several of these counties also include towns on 781 or 508.

Boston's own neighborhoods make up a large share of the area, which is why a 617 number is so strongly linked with the city. Charlestown, East Boston, South Boston and Hyde Park are all part of Boston, so they share the same codes as downtown. If you're looking at one, it most likely came from one of these places or is a mobile line first issued here.

For the codes around Boston, including 508 and 781, see the Massachusetts area codes page.

617 Area Code Time Zone (Eastern Time)

Boston and every 617 and 857 number run on Eastern Time, as does the rest of Massachusetts. Standard time is UTC-5. Daylight saving time, observed from 2:00 a.m. on the second Sunday of March until 2:00 a.m. on the first Sunday of November, is UTC-4.

For teams outside New England, that puts a 617 contact one hour ahead of Chicago and three hours ahead of Seattle all year long, since those cities change their clocks on the same dates.

617 and 857: One Area, Two Area Codes

The 1997 split didn't settle Boston's number supply for long. In a single proceeding, D.T.E. 99-11, covering 508, 617, 781 and 978 at once, the Massachusetts Department of Telecommunications and Energy chose overlays over further splits. Its order of April 25, 2000 directed carriers in eastern Massachusetts to file plans for introducing four new overlay area codes.

For Boston, the new code was 857, which NANPA records as entering service on May 2, 2001. Numbers that already started with 617 kept their area code, and both codes have required ten-digit local dialing ever since.

Day to day, the main difference between the two codes is age. A business with a 617 number isn't any more local than one with 857; it often just got its line earlier. Our 857 area code guide covers the newer code in more detail.

617 Area Code vs ZIP Codes

People looking up a "zip code for area code 617" are usually trying to connect a phone number to a place. The two systems don't line up that way: area codes come from the telephone numbering plan and ZIP codes from the Postal Service, so one area code spans many ZIP codes and the edges rarely match.

Boston, Cambridge and Quincy each have several ZIP codes of their own. A company with a 617 number and an office in Cambridge still needs the Cambridge ZIP code on its mail, because the phone number carries no postal information. To get the right one for a letter or shipping label, search the street address on usps.com.

How to Tell If a Call From 617 Is Legitimate

A 617 caller ID tells you the number was assigned in the Boston area. It doesn't prove who is calling: caller ID can be spoofed, and the FTC notes that scammers often disguise calls to look as if they come from a government agency. A few habits handle most suspicious calls:

• Let unknown numbers go to voicemail. Someone with a real reason to reach you can usually leave a message.
• Don't give in to urgency. The FTC points out that honest businesses give you time to consider an offer.
• Never pay with a gift card, wire transfer, cryptocurrency or payment app just because a caller told you to.
• Keep one-time passcodes and your Social Security number to yourself; no government agency calls out of the blue asking for them.
• Call back through a number you find yourself, such as the one on a statement or the organization's website.

The name shown with a number comes from caller name databases, and our explainer on CNAM caller ID names covers how that works. Report scams at ReportFraud.ftc.gov and unwanted calls at DoNotCall.gov. To stop a repeat caller, block the number in your phone's settings, turn on your carrier's blocking service or use a call-blocking app. Many phones also have a Do Not Disturb setting that sends calls to voicemail during hours you choose, and the FTC notes that some carrier blocking services are free while others charge a fee.

How to Dial a 617 Phone Number

Every local call in the 617/857 area uses ten digits. With (617) 555-0199 as the example:

• Local call within 617 or 857: 617-555-0199.
• Toll or long-distance call from another US area code: 1-617-555-0199.
• From outside the US and Canada: your exit code, then 1 617 555 0199, or +1 617 555 0199 from a mobile phone.

According to NANPA's dialing plan for the area, toll calls within 617 take 1 plus ten digits. Local calls into 617 from a neighboring area code use ten digits, and toll calls from other area codes use 1 plus ten digits.

How to Get a 617 Phone Number for Your Business

Businesses that sell to Boston customers may want a number that looks local there, even if the team works somewhere else. A cloud phone number handles that, because calls follow your people rather than a desk.

Since 617 and 857 cover identical ground, include both in your search. An 857 number is dialed the same way and reaches the same callers.

1. 1Check availability. Look through the Massachusetts area codes Ringflow offers for 617 or 857 numbers.
2. 2Choose where it rings. Forward calls to the Ringflow mobile and desktop apps so the number works from any office or home.
3. 3Accept texts. Turn on business texting so customers can message the number.
4. 4Port instead, if you can. Moving an existing 617 number with number porting keeps printed materials and saved contacts correct.

Ringflow provides local numbers in US area codes along with call forwarding, an auto attendant, business texting and porting, and a free trial lets you test it before committing.

Conclusion

Area code 617 has served Boston since the first numbering plan in 1947, but today it's a compact, city-centered code for Boston, Cambridge, Somerville, Brookline, Newton, Quincy and a few other neighbors. 857 has shared that territory since May 2001, and both run on Eastern Time with ten-digit local dialing.

An unfamiliar 617 call deserves a moment of caution, not alarm. Businesses that want Boston callers to see a local code can look through US area codes and test a number with Ringflow's free trial.

FAQ