The Free Mass Save Home Energy Assessment, Explained (2026)

The Mass Save Home Energy Assessment is a free, roughly two-hour visit where a certified Energy Specialist walks your house, finds where it's leaking heat and money, installs some energy-saving gear on the spot at no charge, and hands you a custom report listing the rebates and financing you now qualify for. It's the gateway. Almost every bigger incentive in Massachusetts, the 75%-off insulation deal, the whole-home heat-pump rebate, the 0% HEAT Loan, sits behind it.

If you've been told "you have to get the assessment first," this is what that actually means, what happens during the visit, and the one part nobody selling you an install tends to mention.

Is the Mass Save Home Energy Assessment really free?

Yes. There's no charge to the homeowner for an eligible 1-to-4 unit home, and the Energy Specialist even installs a batch of products for free while they're there. The catch isn't a hidden bill, it's eligibility. To qualify you need an active residential electric or gas account with a participating utility (Eversource, National Grid, Unitil, and the gas companies all participate). The program is funded through those utility bills, which is also why the roughly 40 Municipal Light Plant towns are a separate story, more on that below.

You don't have to buy anything as a result of the visit. You can take the report, get quotes, and walk away. The assessment costs you nothing and commits you to nothing.

What actually happens during the visit

A standard assessment runs about two hours and follows a predictable arc. The Energy Specialist isn't just eyeballing your attic, they use diagnostic tools and run safety tests on your heating equipment.

Stage	What the Energy Specialist does
Walkthrough	Introduces the process, asks about cold rooms, drafts, and high bills you've noticed
Inspection	Checks insulation, windows, and your heating and cooling equipment, top to bottom
Infrared testing	Uses a thermal camera to read surface temperatures and spot missing or thin insulation behind walls
Combustion safety	Screens your natural gas, oil, or propane appliances for carbon monoxide, drafts, and spillage
Air sealing	Performs no-cost targeted air sealing of the leaky spots they find
Product install	Installs free energy-saving products on the spot
Report	Leaves you with a custom energy report, recommendations plus your eligibility for rebates and incentives

The infrared step is the one homeowners underestimate. A wall can look fine and still be half-empty inside; the thermal camera is how a 1910 Worcester three-decker's cold north wall gets diagnosed without tearing into plaster.

What they install for free on the spot

Expect the Energy Specialist to swap in small efficiency items at no cost during the visit. Per Mass Save, the in-visit installs commonly include smart thermostats, low-flow showerheads, faucet aerators, and energy-saving power strips, plus the targeted air sealing of drafty gaps. None of it is glamorous, but it's free, it's done before they leave, and the air sealing alone often takes a noticeable bite out of winter drafts.

The bigger-ticket work, insulation, a heat pump, a new water heater, isn't done at the assessment. That's what the report sets up.

What the assessment unlocks

This is the real reason to book one. The free visit is the key that opens the incentives that make a project pencil out. The headline items in 2026:

• 75% off approved insulation and air sealing as a standard instant incentive, with 100% off for income-eligible households (the enhanced incentive, based on income and household size). The custom report lists what your home qualifies for.
• The whole-home air source heat-pump rebate, which Mass Save pays per ton of installed capacity. The assessment matters here because the whole-home rebate requires your home to be sufficiently weatherized first, and the assessment is how that gets documented. For the actual dollar amounts and the per-ton math, see our Massachusetts heat pump rebates guide; it owns the rebate numbers so they stay current in one place.
• The 0% HEAT Loan, up to a $25,000 financeable amount at 0% interest (the program sponsors buy down the rate). It covers weatherization, ENERGY STAR replacement windows, and heat-pump projects including heat pump water heaters. Pairing the loan with the rebate is what makes a lot of these upgrades cash-flow neutral instead of a five-figure check.

Sequencing is the point most people get backwards: weatherize first, then heat. A drafty, under-insulated house makes any heating system, especially a heat pump, work harder than it should. Our guide on heat pump sizing for cold-climate Massachusetts gets into why that order matters and how a tighter envelope shrinks the system you need.

The catch nobody mentions

Two things to go in with eyes open.

First, combustion safety testing can stop the show. If the Specialist's CO, draft, or spillage screen flags your gas, oil, or propane appliance as unsafe, that problem has to be addressed before certain work can proceed. That's the program protecting you, not a sales tactic, but it can turn "I wanted insulation" into "I also need to deal with my flue." Better to find it now than during a January cold snap.

Second, the company running your assessment usually hopes to win the install. Many assessments are performed by participating contractors, and that's fine, but you are under no obligation to use them. The report and your rebate eligibility are yours. Take them, get two or three quotes, and let the honest number win. A directory like this one exists precisely so you can compare installers instead of defaulting to whoever showed up with the thermal camera.

Renters, condos, and the ~40 MLP towns

Renters and condo owners can still get value here, the assessment works on 1-to-4 unit buildings, though landlord sign-off is needed for some measures and condos have to sort out what's owner-controlled versus association-controlled.

The bigger exclusion is geography. Around 40 Massachusetts towns get their electricity from a Municipal Light Plant rather than Eversource, National Grid, or Unitil, places like Belmont, Concord, Reading, and Wellesley. Because MLP customers don't pay into the Mass Save surcharge, they aren't eligible for the standard Mass Save assessment and rebates. Most MLPs run their own efficiency program, usually thinner. If that's your town, read why ~40 MA towns aren't Mass Save eligible before you assume the numbers above apply to you.

How to book it and prep your house

Scheduling is a phone call: 1-866-527-SAVE (7283), or book online through Mass Save. A participating contractor can also start the process for you.

To get the most out of the two hours:

• Clear access to the attic hatch, basement, and your heating equipment.
• Have a rough sense of which rooms run cold or have drafts, tell the Specialist.
• Pull a recent electric or gas bill so they can tie recommendations to real usage.
• If you're weighing a heat pump or new boiler, say so up front; weatherization documented now feeds directly into those rebates. Our heat pump rebates guide and the broader HVAC hub cover where that leads next.

FAQ

Is the Mass Save Home Energy Assessment actually free? Yes, for eligible 1-to-4 unit homes with an active electric or gas account at a participating utility. There's no charge for the visit, and the Energy Specialist installs free products while there.

How long does it take? About two hours for a standard single-family home. Larger or more complex homes can run longer.

Do I have to buy anything or use their contractor? No. The assessment commits you to nothing. You keep the report and your rebate eligibility, and you're free to get competing quotes and choose your own installer.

What do they install for free? Typically small efficiency items, smart thermostats, low-flow showerheads, faucet aerators, and energy-saving power strips, plus no-cost targeted air sealing of drafty spots.

What if my town isn't on Mass Save? If you're in one of the ~40 Municipal Light Plant towns, you're not eligible for the standard Mass Save assessment; your MLP likely runs its own program. See our MLP towns guide.

What does the assessment unlock? The custom report lists your eligibility for the 75%-off insulation incentive (100% if income-eligible), the whole-home heat-pump rebate, and the 0% HEAT Loan up to $25,000, the incentives that make bigger upgrades affordable.