Seven layers deep: Massachusetts's incentive stack
A modest but genuinely useful state credit
Under MGL Chapter 62, Section 6(d), Massachusetts offers a state income tax credit worth 15% of your net system cost, capped at $1,000, claimed via Schedule EC. Since any system costing $6,667 or more hits that cap, most residential installations effectively receive a flat $1,000 credit. It's non-refundable but can be carried forward for up to three years if your tax liability is smaller than the credit in the year you install. Check your federal ITC status too, since eligibility for it changed heading into 2026. Borrowing shifts when you pay, and the combined loan and rebate timing tool lays out the payments behind that shift.
Two tax exemptions doing real work
Solar equipment is fully exempt from the state's 6.25% sales tax at the point of sale, and under MGL Chapter 59, Section 5, clause 45, the added value your system gives your home is excluded from property tax assessment for 20 years, one of the longest exemption periods in the country. Per the Massachusetts Department of Revenue's own Division of Local Services guidance, this exemption is generally capped at systems sized to produce no more than 125% of the property's annual electricity needs, so an unusually oversized system relative to your household's own usage could fall outside the exemption's scope. Neither requires much homeowner effort otherwise: the sales tax exemption applies automatically on your contract, and the property tax exemption generally doesn't require a separate application in most municipalities, though confirming with your local assessor is still worthwhile. Run your specific numbers through the property tax exemption savings calculator to see the total over time. For the source behind this number, see the Massachusetts Department of Revenue's own Division of Local Services guidance.
SMART pays for production, not just export
The Solar Massachusetts Renewable Target program is structured as a declining block incentive, paying a fixed rate for every kilowatt-hour your system produces, currently around 3 cents per kWh for most residential systems up to 25 kW, over a 10-year term. This is fundamentally different from net metering, which only credits excess power you send to the grid. SMART pays out on total production, so it adds value even in months where you're using most of what you generate yourself. Use the performance-based incentive calculator to model this over the full 10-year term. The net metering explains the terms behind this estimate in plain language.
Net metering is strong, but not guaranteed to stay that way
All three investor-owned utilities, Eversource, National Grid, and Unitil, are required under state law to offer net metering, crediting exported power at or near the full retail rate, typically landing around 90% to 98% after a small number of non-bypassable charges are excluded. On December 15, 2025, the Massachusetts Department of Public Utilities opened docket D.P.U. 25-200, a broader investigation into gas and electric delivery charges and bill redesign, not a dedicated net metering docket; one of its five specific objectives is examining whether the value of the net metering credit should be adjusted, with a stated goal of reducing costs associated with the program. No cut has been finalized, but it's a genuine live question worth tracking if your installation timeline has flexibility. With your rebate total in hand, the combined loan and rebate timing tool shows the monthly payment on the amount you still need to borrow.