Free Insulation Mass Save: Get 75–100% Off in 2026
Massachusetts homeowners can get insulation for pennies on the dollar through Mass Save. Income-qualified households pay nothing. Here's the full breakdown — who qualifies, what's covered, and how to get started.
Key Takeaways
- Mass Save covers 75% of insulation costs for all eligible homeowners
- Income-qualified households get 100% free insulation — zero out of pocket
- Add the federal 25C tax credit to cut your remaining cost by another 30%
- Starts with a free Home Energy Assessment — no obligation
Here's something most Massachusetts homeowners don't realize: you can insulate your entire home for as little as $500–$1,500 out of pocket. And if your household income qualifies, you pay nothing at all.
Mass Save — the statewide energy efficiency program funded by your utility company — picks up 75% of the tab for insulation. That's not a typo. On a $4,000 insulation project, you'd pay around $1,000. On a $6,000 project, about $1,500.
For income-qualified households? The entire cost is covered. Materials, labor, air sealing — all of it. This is the single easiest entry point into Massachusetts energy rebates, and it's available right now.
How Mass Save Insulation Works
Mass Save doesn't hand you a check and wish you luck. The program handles the entire process — from assessing your home to hiring the contractor to installing the insulation. Your job is basically to schedule the appointment and be home for it.
It starts with a free Home Energy Assessment. A certified energy specialist visits your home, checks your current insulation levels, identifies air leaks with a blower door test, and tells you exactly what work your home needs. They'll also swap out old light bulbs, install smart power strips, and check your appliances — all included.
After the assessment, you'll get a recommendation for insulation work. If you want to move forward, Mass Save coordinates the contractor, schedules the installation, and applies the rebate automatically. You never file paperwork or chase a reimbursement check. The 75% discount is applied before you pay.
How Much Does Mass Save Insulation Actually Cost?
The sticker price for whole-home insulation in Massachusetts typically runs $4,000 to $8,000. But with Mass Save covering 75%, your actual out-of-pocket cost drops dramatically. Here's what the numbers look like:
2026 Mass Save Insulation Costs (After 75% Rebate)
| Insulation Type | Standard | Income-Qualified | Typical Total Cost | Your Cost (Standard) |
|---|---|---|---|---|
| Attic Insulation | 75% covered | 100% covered | $2,000–$3,500 | $500–$875 |
| Wall Cavity Insulation | 75% covered | 100% covered | $2,500–$4,500 | $625–$1,125 |
| Basement/Crawl Space | 75% covered | 100% covered | $1,500–$3,000 | $375–$750 |
| Air Sealing | 75% covered | 100% covered | $500–$1,500 | $125–$375 |
Most Homes Get Multiple Areas Done
A typical Mass Save insulation project covers attic insulation, air sealing, and often basement rim joists — all in the same visit. The 75% rebate applies to the entire scope of work, not just one area.
Who Qualifies for Mass Save Insulation?
Almost every Massachusetts homeowner qualifies for the 75% rebate. The bar is low on purpose — the utilities fund this program and want as many homes insulated as possible (well-insulated homes use less energy, which reduces strain on the grid).
Here's what you need:
- A Massachusetts address with an active electric or gas account through Eversource, National Grid, Unitil, Cape Light Compact, Berkshire Gas, Liberty Utilities, or a participating municipal utility
- A home that needs insulation — the energy assessment determines this (most older MA homes do)
- Homeowner or landlord permission — renters can start the process but need their landlord to approve the work
That's it. No income requirements for the 75% rebate. No special application. No lottery.
Income-Qualified: 100% Free Insulation
If your household income falls at or below 60% of the Area Median Income (AMI), Mass Save covers the full cost. At 80% AMI, you'll receive enhanced rebates above the standard 75%. The thresholds vary by county, but as a rough guide:
- 60% AMI (2 people): ~$51,000–$57,000 depending on county
- 60% AMI (4 people): ~$63,750–$71,250 depending on county
- 80% AMI (2 people): ~$68,000–$76,000 depending on county
- 80% AMI (4 people): ~$85,000–$95,000 depending on county
Not sure where you fall? Call your utility or check our income-qualified eligibility guide. The assessment is free either way, and the assessor can help determine your eligibility on the spot.
What Types of Insulation Does Mass Save Cover?
Mass Save covers most insulation types that make sense for Massachusetts homes. The energy assessor will recommend specific materials based on your home's construction, age, and existing insulation levels.
Attic Insulation
The #1 priority for most homes. Blown-in cellulose or fiberglass fills gaps and brings your attic to R-49 or higher.
- • Biggest energy savings per dollar
- • Completed in 2–4 hours
- • No disruption to living space
- • R-49+ target for Massachusetts climate
Wall Cavity Insulation
Dense-pack cellulose is injected into exterior walls through small holes that are patched after. Ideal for older homes with empty wall cavities.
- • Fills hollow walls without removing drywall
- • Reduces drafts significantly
- • 1-day installation for most homes
- • Patch holes are nearly invisible
Basement & Crawl Space
Rigid foam board or spray foam on basement walls and rim joists stops cold air from entering through your foundation.
- • Eliminates cold floors above
- • Reduces moisture and mold risk
- • Rim joist sealing is high-impact
- • Often done same day as attic
Air Sealing
Caulking, weatherstripping, and foam sealing around penetrations, gaps, and cracks. Always done alongside insulation.
- • Stops drafts at the source
- • Typically included with insulation work
- • Addresses attic bypasses and plumbing chases
- • Measurable improvement on blower door test
How to Get Mass Save Insulation: Step by Step
Schedule Your Free Home Energy Assessment
Call your utility or visit the Mass Save website to book a no-cost Home Energy Assessment. Appointments are typically available within 2–4 weeks. The visit takes about 2–3 hours.
Get Your Assessment & Recommendations
The assessor checks your attic, walls, basement, and windows. They'll use a blower door test to measure air leakage and thermal imaging to spot insulation gaps. You'll get a detailed report with specific recommendations.
Review Your Quote (With the 75% Rebate Already Applied)
Mass Save coordinates the insulation contractor and provides a quote showing the full cost, the 75% rebate, and your out-of-pocket amount. No surprises — you see the final number before agreeing to anything.
Installation Day
A Mass Save-approved contractor installs the insulation. Most projects finish in a single day. Attic and basement work causes minimal disruption — you can stay home during the process.
Pay Your 25% Share (and Claim the Tax Credit)
You pay only your portion — the 25% remaining after the Mass Save rebate. Save your receipt to claim the federal 25C tax credit the following tax season for an additional 30% off your out-of-pocket cost.
Stack Your Savings: Mass Save + Federal Tax Credit
This is where the math gets really good. After Mass Save pays 75%, you can claim the federal Energy Efficient Home Improvement Credit (25C) for 30% of your remaining out-of-pocket costs, up to $1,200 per year for insulation.
Real Example: Whole-Home Insulation
* That's $962 for a project that would cost $5,500 without incentives — an 83% discount.
0% Financing Available
Can't cover the 25% upfront? Mass Save's HEAT Loan offers 0% interest financing with terms up to 7 years. You could insulate your entire home and spread the $1,000–$1,500 cost over monthly payments of $12–$18.
Is Mass Save Insulation Actually Worth It?
Short answer: yes, and it's not close.
A properly insulated Massachusetts home uses 15–25% less energy for heating and cooling. On an average monthly energy bill of $250–$300, that's $40–$75 per month in savings — or $480–$900 per year.
At a final cost of $962 (from our example above), the insulation pays for itself in about 13–24 months. After that, the savings are pure profit for the remaining 20+ year lifespan of the insulation.
But energy savings aren't the only reason homeowners go through with it:
- Comfort: No more cold rooms, drafts, or ice dams. Your home stays a consistent temperature.
- Noise reduction: Insulation doubles as soundproofing, especially in wall cavities.
- Home value: Energy-efficient upgrades are a selling point. Buyers notice lower utility bills.
- Prerequisite for heat pumps: Mass Save often requires insulation before approving heat pump rebates, so getting it done now opens the door to even bigger savings later.
Why Insulation Should Be Your First Energy Upgrade
If you're thinking about heat pumps, solar panels, or other energy upgrades, insulation should come first. Here's why: every other upgrade works better in a well-insulated home.
A heat pump in a drafty, poorly insulated house has to work harder — which means higher electricity bills and potentially needing a larger (more expensive) system. Insulating first means you can install a smaller heat pump that costs less, runs less, and lasts longer.
Mass Save knows this. That's why the insulation rebate is 75% (the highest percentage rebate they offer) and why energy assessors often recommend insulation before approving other upgrades.
The Bottom Line
Mass Save insulation is the most straightforward energy rebate in Massachusetts. The process is simple, the savings are real, and the 75% rebate makes it accessible to nearly everyone.
For income-qualified households, it's completely free. For everyone else, the combination of Mass Save's 75% rebate and the federal 25C tax credit can cut a $5,500 project down to under $1,000.
The first step costs nothing: schedule your free Home Energy Assessment and find out what your home needs. There's no obligation, and you'll leave the appointment knowing exactly what you'd pay.
Ready to Get Started?
See the full breakdown of Massachusetts insulation rebates and find out what your home qualifies for.
Frequently Asked Questions
Is Mass Save insulation really free?
For income-qualified households (at or below 60% of Area Median Income), Mass Save covers 100% of insulation costs — materials, labor, and air sealing included. Standard-income homeowners receive 75% off, which typically brings a $4,000–$6,000 project down to $1,000–$1,500 out of pocket.
What types of insulation does Mass Save cover?
Mass Save covers attic insulation (blown-in cellulose or fiberglass), wall cavity insulation, basement and crawl space insulation, rim joist insulation, and air sealing. The specific materials depend on your home's construction and what the energy assessor recommends.
Do I need a home energy assessment first?
Yes. A free Mass Save Home Energy Assessment is the required first step. The assessor evaluates your home's current insulation levels, identifies air leaks, and determines exactly what work qualifies for rebates. The assessment itself costs you nothing.
How long does the insulation installation take?
Most Mass Save insulation projects are completed in one day. Larger homes or projects that include wall cavity insulation may take two days. The assessment is a separate visit that typically takes 2–3 hours.
Can I combine Mass Save insulation rebates with federal tax credits?
Yes. After your Mass Save rebate, you can claim the federal Energy Efficient Home Improvement Credit (25C) for 30% of your remaining out-of-pocket insulation costs, up to $1,200 per year. This can reduce your final cost to just a few hundred dollars.
Does Mass Save insulation work for renters?
Yes, but you need your landlord's written permission. The rebate goes to the property owner, but renters can initiate the process by scheduling the Home Energy Assessment. Many landlords agree once they see the 75–100% cost coverage.