Mass Save Smart Thermostat Rebate 2026, The Real Total Nobody Adds Up

The 2026 Mass Save smart thermostat rebate is not a single $100 check. For most eligible Massachusetts homeowners it is a stack: $100 instant rebate on a qualifying ENERGY STAR smart thermostat, plus $50 to $100 enrollment bonus for connecting that thermostat to Mass Save's ConnectedSolutions demand response program, plus $20 per thermostat every summer after that. Over a 10-year thermostat life, that is up to roughly $400 per device, not $100. If you live in one of the ~40 Municipal Light Plant towns, or your setup is a heat-only boiler or a window AC, most of that stack does not apply to you, and every top-ranking guide on this question skips right past that.

This is the version that reflects what Mass Save actually pays in 2026, cross-checked against masssave.com and the individual utility program pages. It is not the marketing sheet.

The $100 instant rebate, plainly

Mass Save (the joint efficiency program of Eversource, National Grid, Unitil, Cape Light Compact, Berkshire Gas, and Liberty Utilities) offers up to $100 per thermostat on an ENERGY STAR certified smart thermostat. Non-smart 7-day programmables are also on the sheet at up to $25, though there is almost no reason to buy one of those in 2026.

Key rules for the $100:

• Three per account, every three years. You can rebate a whole zoned house at once, but a fourth thermostat in year one is on you.
• Instant, not mail-in. You claim it on the Mass Save Marketplace at checkout, at a participating retailer with an in-store code, or through an online application after purchase.
• Installation window: January 1 through December 31, 2026. Applications must be in by February 28, 2027.
• ENERGY STAR is the actual gate. "Smart" alone is not enough. If a model is not on the ENERGY STAR product list, it does not get the $100.

That last one matters. Not every Wi-Fi thermostat on Amazon is ENERGY STAR certified, and Mass Save's rebated product list is narrower than the retail category.

The part nobody adds up, ConnectedSolutions

This is the interesting money. ConnectedSolutions is Mass Save's active demand response program: you enroll your smart thermostat, and on summer weekday afternoons when the New England grid is straining, your utility precools your house and then lets it drift up by no more than 4°F for two to three hours. There are about 15 events between June 1 and September 30, all between 3 pm and 8 pm on non-holiday weekdays. You can opt out of any single event from the thermostat.

What you get paid:

• $50 enrollment bonus if you are on a standard residential electric rate (R-1).
• $100 enrollment bonus if you are on the income-eligible discount rate (R-2). This is the same rate that already gives low-income households a monthly bill discount, and it doubles your ConnectedSolutions signup check.
• $20 per thermostat, per summer season, for as long as you stay enrolled.
• For a business account on G-1, G-2, or G-3 electric rates, it is $50 enrollment plus $200 per summer, which is a different animal.

Compound it. A homeowner who buys one qualifying smart thermostat, uses the $100 instant rebate, enrolls in ConnectedSolutions, and stays enrolled for the useful life of the device (call it eight to ten years):

• $100 instant rebate
• $50 enrollment bonus
• $20 × 10 summers = $200

That is $350 back on one thermostat. If you are on the R-2 rate the enrollment bonus is $100, taking the total near $400. Zone the house with three, and the ten-year cash back for the average household clears $1,000. None of the top-ranking pages for this query stack those numbers together.

Which thermostats actually qualify (both programs)

The instant rebate list is not identical to the ConnectedSolutions list. A thermostat can be ENERGY STAR certified (good for the $100) without being on a utility's BYOD dispatch list (good for ConnectedSolutions), and vice versa. Below are the brands confirmed on both Mass Save's rebated-products page and the ConnectedSolutions eligible-devices page for 2026. Specific SKUs change as manufacturers release new models, so check your exact model number at purchase.

Brand family	Common qualifying models	$100 instant rebate	ConnectedSolutions BYOD
Google Nest	Nest Thermostat, Nest Learning Thermostat (Gen 4)	Yes	Yes
ecobee	Smart Thermostat Essential, Enhanced, Premium (plus eco+ enrolled variants)	Yes	Yes
Sensi (Copeland/Emerson)	Sensi Classic, Touch 2, Lite	Yes	Yes
Honeywell Home	T5 Gen 2, T6 Pro, X2S, X7S, X8S (Total Connect Comfort and Lyric families)	Yes	Yes
Amazon	Amazon Smart Thermostat	Yes	Yes, Eversource electric only
Alarm.com, Lux, Trane, Vivint	Various Wi-Fi models	Varies by SKU (check ENERGY STAR status)	Yes on National Grid, most other sponsors

Two practical notes.

The Amazon Smart Thermostat is a real value pick, cheap, ENERGY STAR certified, and gets the $100. But its BYOD dispatch path has historically been Eversource-only in Massachusetts. If you are a National Grid electric customer and you want the ConnectedSolutions checks, a Nest, ecobee, Honeywell, or Sensi will get you further.

ecobee's eco+ enrollment is how ecobee routes into ConnectedSolutions. Some retailers ship an ecobee with eco+ off by default. Turn it on and link to your utility during setup, or you will collect the $100 and leave the annual $20 on the table.

Heat pump vs central AC vs window units

ConnectedSolutions cares about your cooling equipment, not your fuel. To enroll a thermostat, it must be connected to a central air conditioner or a central heat pump (ducted or ductless). That means:

• Heat pump homes qualify. A cold-climate air-source heat pump is exactly the load the grid wants managed on a July afternoon, and paying customers to precool with heat pumps is one of the reasons the program exists. Pair well: many households doing an oil-to-heat-pump conversion already have to buy new thermostats, so the $100 + ConnectedSolutions stack is essentially free money on top of the whole-home rebate covered in our sibling piece on Mass Save heat pump rebates.
• Central AC only homes qualify even if the heat is a gas boiler or furnace.
• Window units do not qualify for ConnectedSolutions, and neither does a smart thermostat that only controls heat. If you have a gas boiler with radiators and no central AC, you can still buy an ENERGY STAR thermostat that controls the boiler and claim the $100 instant rebate, but you cannot enroll it in ConnectedSolutions and there is no annual $20.
• Mini-splits with their own handheld controllers do not enroll unless you add a compatible smart thermostat interface. Most homeowners skip this, and Mass Save is not paying you for the built-in remote.

The one honest downside of ConnectedSolutions on a heat pump: the summer event window (3 pm to 8 pm weekdays) is not always convenient, and on the hottest days of the year the "no more than 4°F setback" can still be enough to notice indoors. Opt out for the day if you have a house full of guests. If you opt out constantly, Mass Save can unenroll you.

What changes if you live in a Municipal Light Plant town

About 40 Massachusetts towns get their electricity from a Municipal Light Plant (MLP) rather than Eversource, National Grid, or Unitil. Belmont, Concord, Reading, Wellesley, Braintree, Norwood, Mansfield, Hingham, Holyoke, Westfield, Taunton, and Peabody are on this list, along with many smaller towns. MLP customers do not pay into the Mass Save energy efficiency charge, and they are not eligible for either the $100 instant rebate or ConnectedSolutions.

What you can get instead varies wildly by MLP. Concord Municipal Light Plant, Reading Municipal Light Department, and Belmont Municipal Light Department each run their own efficiency programs; some pay small smart thermostat rebates, some do not, and their versions of demand response are separate programs run through their own vendors. For details, our Mass Save exclusion guide for MLP towns covers the general lay of the land and which utilities offer what. There is one wrinkle: if your MLP town also has a gas utility served by an investor-owned utility (Concord is a common example), a gas-fired boiler or furnace with a smart thermostat can sometimes access Mass Save's gas-side rebates even though the electric side is out. Ask your gas utility, not your MLP.

Do you need a Mass Save Home Energy Assessment first?

For the $100 instant rebate at retail, no. You can buy an eligible thermostat on the Mass Save Marketplace or from a participating retailer today and claim the $100 at checkout without ever booking an assessment.

For a free thermostat installed by a Mass Save Home Energy Specialist, yes, that is the point of booking a Mass Save Home Energy Assessment in the first place. The specialist may install a smart thermostat on the spot at no charge as part of the visit, along with the standard package of LEDs, aerators, and pipe wrap. Not every visit ships one (it depends on your existing setup and the current inventory the specialist is carrying), but it is a legitimate no-cost path and it also opens the door to the bigger insulation and heat pump incentives. If you are planning heat pump work anyway, book the assessment first for that reason alone.

What to buy and where

For most Massachusetts homeowners in 2026, the honest recommendation is:

• If you want the highest ceiling on features and you have a central heat pump or central AC, an ecobee Enhanced or Premium, or a Nest Learning Thermostat, both clear both rebate paths and both play well with heat pump staging.
• If you are cost-conscious and on Eversource electric, the Amazon Smart Thermostat is the cheapest legitimate path to the full $100 + $50 + $20/year stack.
• If you are on National Grid electric and want cheap plus ConnectedSolutions, Sensi Touch 2 or a Honeywell T6 Pro land in the same value bracket.
• If you have a gas boiler with no central AC, buy any ENERGY STAR smart thermostat you like for the $100, and skip the ConnectedSolutions expectation.

Buy through the Mass Save Marketplace when you can. The instant discount comes off at checkout and there is no rebate form. If you buy at a big-box retailer, ask for the in-store Mass Save code at the register (they know the drill).

FAQ

Does Mass Save give free smart thermostats? Sometimes, yes. A Mass Save Home Energy Specialist may install one at no charge during your free Home Energy Assessment, alongside LEDs and other basic measures. It is not guaranteed on every visit, but booking the assessment is the only path to a truly free unit.

Which brands qualify for the Mass Save $100 smart thermostat rebate in 2026? The rebated products list includes ecobee (Essential, Enhanced, Premium), Google Nest (Nest Thermostat and Nest Learning Gen 4), Sensi (Classic, Touch 2, Lite), Honeywell (T5 Gen 2, T6 Pro, X2S, X7S, X8S), and the Amazon Smart Thermostat. The single hard rule underneath the list is ENERGY STAR certification.

How much does ConnectedSolutions pay for a thermostat? $50 at enrollment on the standard R-1 electric rate, $100 at enrollment on the income-eligible R-2 rate, and $20 per thermostat per summer thereafter. Business accounts on G-1/G-2/G-3 rates get $50 enrollment plus $200 per summer.

Can I get the thermostat rebate if I live in a Municipal Light Plant town? Not through Mass Save. MLP customers are not eligible for the $100 instant rebate or ConnectedSolutions. Some MLPs run their own smaller thermostat rebate; the amount and rules vary by town.

Does ConnectedSolutions take control of my thermostat? Only during about 15 summer weekday afternoon events, and only within a 4°F setback. You can opt out of any single event from the thermostat or the app. If you opt out too often, your utility can unenroll you and stop paying the $20. Heat pump owners in particular should enroll: heat pumps are exactly the cooling load ConnectedSolutions is designed to manage, and pairing enrollment with a new install (ask your Mass Save Heat Pump Installer Network contractor to do it at commissioning) is the least friction path.

Get the thermostat rebate priced into your HVAC quote

If you are pricing a new heat pump, central AC, or a control retrofit, the thermostat rebate stack should be built into the quote from day one, not added as an afterthought. Tell us about your project and we will route you to vetted MA installers who quote the thermostat, the Mass Save paperwork, and the ConnectedSolutions enrollment as one line item: get a free estimate. If you just want to browse local HVAC pros first, you can also start from our HVAC hub.