In Massachusetts the heating season runs from September 15 to May 31. During those dates your landlord has to keep the apartment at a minimum temperature, and outside them there is no temperature requirement at all.
But your city can move those dates, and two cities near Boston have. Cambridge and Medford both start on September 30 rather than September 15, which means that for the last two weeks of September a renter in Somerville is owed heat and a renter one mile away in Cambridge is not.
Here is where each city actually stands. All dates below were checked against the cities' own pages on September 8, 2026.
Heating season dates, city by city
| City | Heat required from | Until | Different from the state? |
|---|---|---|---|
| Massachusetts default | September 15 | May 31 | 105 CMR 410.180 |
| Boston | September 15 | May 31 | No, but see the note below |
| Cambridge | September 30 | May 18 (2026) | Yes, both ends moved |
| Medford | September 30 | May 15 | Yes, both ends moved |
| Somerville | September 15 | May 31 | No |
| Brookline | Not published | Not published | Unknown, call 617-730-2300 |
| Newton | Not published | Not published | Unknown, call 617-796-1420 |
The Brookline and Newton rows are not an oversight. Neither city publishes its heating season dates anywhere I could find. That almost certainly means both are on the state schedule, because a board of health that changes the dates is supposed to post the change. But "almost certainly" is not the same as confirmed, and if you are in either city and the answer matters to you this month, the phone call is worth five minutes.
Cambridge's May 18 date is specific to 2026. Cities set the spring end date each year based on the forecast, so it will be a different date next spring. The September 30 start is the one to remember.
Why the dates differ at all
The rule is 105 CMR 410.180, part of the State Sanitary Code. It sets the season at September 15 to May 31, and it also hands local boards of health a limited power to shift it.
A city can move either end by up to fifteen days. It can end the season early, but no earlier than May 15, and it can delay the start, but no later than September 30. That is the whole range, and no city in Massachusetts can require heat before September 15.
Cambridge and Medford have both used that power to its limit at the front end. Cambridge Inspectional Services set the 2026 season to resume on September 30, and ended the spring side on May 18 rather than May 31. Medford's Health Department states the season "ends on May 15th and starts on September 30th," which is the maximum shift the regulation allows at both ends.
Somerville stayed on the state dates, which means you genuinely cannot guess: two cities that share a border are three weeks apart on when the heat has to come on.
One piece of history explains a lot of the confusion you will find online. The season used to end on June 15, and a 2023 amendment moved it to May 31. A fair amount of published material still carries the old date, including, as it turns out, the City of Boston's own website.
Boston's pages disagree with each other
Boston has not changed its heating season. It is on the state dates, September 15 to May 31.
The complication is that two different Boston.gov pages give two different answers. The city's winter heating season page, last updated on May 18, 2026, says the heating season "starts on Sept. 15 and ends on June 15." The city's top ten things tenants and landlords need to know, last updated on August 27, 2026, says heat must be provided "between Sept. 15 and May 31."
The August page is the correct one. The May page is carrying the pre-2023 end date.
The discrepancy is an ordinary content problem on a large municipal site, and it will probably be fixed. It is worth knowing about for one practical reason: if you are arguing with a landlord in early June and you are both citing City of Boston pages, you may be reading different pages. When the two disagree, the regulation is what actually governs.
If your city doesn't publish a date
If your city publishes nothing, the state dates apply. A board of health that alters the season is supposed to post that change on the municipal website, so silence usually means no change was made.
But the only way to be certain is to ask your local board of health or inspectional services department directly. It is a quick call and they will tell you.
And note what the season does not control. Being outside the heating season does not mean your apartment is allowed to be uninhabitable, and it does not suspend your landlord's other obligations. It only governs the minimum temperature requirement.
What temperature your apartment has to reach
During the season, the apartment has to reach at least 68°F by day and 64°F overnight, with a 78°F ceiling on the system so it can't run too hot either.
Who pays for the heat is a separate question from whether it has to be on, and it is decided by your lease rather than by the regulation. Both are covered in more detail in our guides to what's included in Boston apartment rent and how to read a Boston apartment lease.
If it's cold and the season hasn't started yet
The season start governs the minimum temperature requirement, but it does not mean your landlord has no obligations to you until then. An apartment still has to be fit to live in, a broken heating system is still a defect the landlord has to repair, and a genuine cold snap in mid September is a reasonable thing to raise even if the calendar has not caught up.
What that is worth in your particular situation depends on facts this article does not have. If your apartment is cold and the conversation with your landlord is not going anywhere, the route is your local board of health or inspectional services, which can inspect and issue orders. Our guide on who to call about a landlord problem in Boston covers where a complaint actually goes and in what order.
Where this stops being general advice
- Whether your apartment is unlawfully cold right now. That turns on the actual temperature, the time of day, the state of the heating system, and your city's dates. An inspection settles it, an article cannot.
- What your dates are if you are in Brookline, Newton, or a city not listed here. Six cities were checked for this piece. There are 351 municipalities in Massachusetts.
- Whether a landlord has breached habitability, and what that is worth.
For any of those, start with your local board of health or inspectional services department, and MassLegalHelp is a good free source on tenant rights.
Frequently asked questions
When does the heating season start in Massachusetts? September 15 under the State Sanitary Code, and it runs to May 31. Your city can delay the start by up to fifteen days, so in some places it is September 30.
When does the heating season start in Cambridge? September 30. Cambridge Inspectional Services set the 2026 season to resume on that date, two weeks later than the state default.
When does the heating season start in Medford? September 30, and it ends on May 15. Medford has shifted both ends of the season by the maximum the regulation allows.
Is Somerville the same as Cambridge? No. Somerville uses the state dates, September 15 to May 31, so heat is required there two weeks earlier than in Cambridge.
Can a city really change the dates? Yes, within limits. Under 105 CMR 410.180 a local board of health can end the season no earlier than May 15 and delay the start no later than September 30. It cannot go beyond that in either direction.
What temperature does my apartment have to be? At least 68°F from 7:00 a.m. to 11:00 p.m. and at least 64°F from 11:01 p.m. to 6:59 a.m. The system is also capped at 78°F.
My city doesn't publish its dates. What applies? The state dates, September 15 to May 31, unless your board of health has altered and posted a change. Call your board of health if it matters to you this month.
It's freezing and the season hasn't started. Do I have any rights? The season start governs the temperature requirement, but your apartment still has to be habitable and a broken heating system is still a repair issue. Raise it with your landlord, and if that goes nowhere, your local board of health can inspect.
Sources, and when this was checked
All city dates were checked on September 8, 2026 against each municipality's own page.
- 105 CMR 410.180 guidance, Mass.gov. State heating season and minimum temperatures.
- City of Cambridge Inspectional Services. 2026 heating season changes.
- City of Medford Health and Human Services. Medford heating season dates.
- City of Somerville ISD Health Division. Somerville temperature requirements.
- Boston.gov winter heating season and Boston.gov top ten things.
Heating season dates are re-set annually, so check your city's page before relying on a spring end date.
This article is informational and isn't legal advice. Whether a specific apartment is unlawfully cold, and what to do about it, depend on facts this article doesn't have, so confirm with your local board of health, MassLegalHelp, or a tenant-rights attorney.