Last Updated: May 16, 2026 | Reviewed by: Dylan DeSantis, SolarMetric
Quick Answer
The average solar installation in Massachusetts costs $3.16 per watt, or $25,000–$38,000 for a typical 8–12 kW home system. The federal ITC expired December 31, 2025, but Massachusetts offsets this with SMART 3.0 ($0.03/kWh for 20 years), full retail-rate net metering, a 15% state tax credit (up to $1,000), and a 20-year property tax exemption. Expect an 8–9 year payback for most systems.
Average Solar Installation Cost in Massachusetts (2026)
Massachusetts homes typically need an 8–12 kW solar system. At the statewide average of $3.16 per watt installed, here’s what that costs before and after state incentives:
| System Size | Installed Cost (Before Incentives) | After State Incentives* | Est. Annual Benefit** | Payback Period |
|---|---|---|---|---|
| 6 kW | $18,960 | $17,190 | $2,537 | 6.8 years |
| 8 kW | $25,280 | $23,252 | $3,383 | 6.9 years |
| 10 kW | $31,600 | $29,316 | $4,229 | 6.9 years |
| 12 kW | $37,920 | $35,380 | $5,075 | 7.0 years |
*After-incentive cost includes the Massachusetts 15% state income tax credit (capped at $1,000) and the 6.25% sales tax exemption applied to the equipment portion of the system (equipment estimated at 65% of total installed cost).
**Annual benefit = net metering savings + SMART 3.0 income. Calculated as: (system kW × 4.0 peak sun hours/day × 30 days × 0.85 system efficiency × $0.3151/kWh × 12 months) + (system kW × 4.0 hrs × 365 days × 0.85 × $0.03/kWh SMART rate). Electricity rate is the EIA Massachusetts residential average for Q1 2026.
⚠️ Note: The federal 30% Residential Clean Energy Credit (Section 25D/ITC) expired for new residential installations after December 31, 2025. It is not included in the after-incentive figures above. See our federal tax credit guide for full details on what changed.
Massachusetts costs run $0.10–$0.20/watt above the national average ($2.95–$3.00/watt). Higher labor rates, complex permitting requirements in many municipalities, and the structural challenges of older New England homes—slate roofs, steep pitches, masonry chimneys—push costs up relative to Sun Belt states.
Cost Per Watt in Massachusetts
The statewide average is $3.16/watt, with installer quotes typically ranging from $2.95 to $3.40/watt. What pushes your quote toward the high end:
- Panel brand and tier: Premium monocrystalline panels (REC, Q Cells, Panasonic) add 10–20¢/watt vs. standard options
- Roof complexity: Slate, clay tile, or metal roofing adds $1,000–$3,500 in labor; steep pitches require additional safety equipment
- System size: Larger systems cost less per watt — economy of scale typically saves $0.10–$0.20/watt on 12 kW vs. 6 kW
- Battery storage add-on: Adding a 10–13 kWh battery (e.g., Tesla Powerwall or Enphase IQ Battery) adds $8,000–$14,000 to the total cost
For a full breakdown of what drives national average pricing, see our solar panel cost guide.
Massachusetts Solar Incentives (2026)
Massachusetts has one of the most layered state incentive stacks in the country. Here’s what’s available now:
1. SMART 3.0 Program — $0.03/kWh for 20 Years
The Solar Massachusetts Renewable Target (SMART) 3.0 program pays a flat $0.03 per kWh your system generates for 20 years, paid on top of your net metering credits. It’s administered through Eversource, National Grid, and Unitil.
For a 10 kW system generating approximately 12,400 kWh/year, SMART earns about $372/year — or $7,440 over 20 years. That’s a guaranteed income stream locked in at the time your system receives Permission to Operate, regardless of future policy changes.
SMART adders available in 2026:
– Battery storage pairing: +$0.04/kWh on top of base rate
– Low-income households: base rate of $0.06/kWh (double the standard)
2. Massachusetts State Income Tax Credit — 15%, Up to $1,000
Massachusetts offers a 15% state income tax credit on your solar system cost, capped at $1,000. The credit is non-refundable but can be carried forward for up to three years. It applies to systems installed on your primary Massachusetts residence. On a $31,600 system the maximum $1,000 credit is reached at system costs above $6,667.
3. Sales Tax Exemption — 6.25% Off Equipment
Solar installations are fully exempt from Massachusetts’ 6.25% sales tax. The exemption applies automatically at purchase — no paperwork required. On a typical 10 kW system where approximately 65% is equipment cost, you save about $1,285 you’d otherwise pay at the register.
4. 20-Year Property Tax Exemption
Installing solar does not increase your property taxes in Massachusetts. State law mandates a 100% property tax exemption on the added value of your solar system for 20 years from the date the system is commissioned and connected to the grid. If you sell your home, the new owner inherits the remaining years of the exemption.
5. Federal ITC — No Longer Available for 2026 Residential Installations
Critical update: The federal 30% Residential Clean Energy Credit (IRS Form 5695, Section 25D) expired for new residential solar installations after December 31, 2025. This change was enacted through the One Big Beautiful Bill (Public Law 119-21, signed July 4, 2025).
- Systems installed in 2025: Still eligible — claim the 30% credit when filing your 2025 federal taxes
- Systems installed in 2026 or later: Not eligible for Section 25D
- Third-party-owned systems (leases, PPAs): Installers may still claim the commercial Section 48E credit through 2027, which they may pass through as lower monthly rates
The loss of the federal ITC adds roughly 1.5–2 years to the payback period compared to 2025 buyers.
Net Metering in Massachusetts
Massachusetts offers full 1:1 retail-rate net metering for residential systems up to 25 kW (Class I) through all three investor-owned utilities. When your system produces more than you use, the surplus goes to the grid and you receive a credit at the full retail delivery rate:
| Utility | Primary Service Area | Approx. Net Metering Credit Rate (2026) |
|---|---|---|
| Eversource | Eastern MA (Boston, Cape Cod, South Shore, North Shore) | ~$0.2836/kWh |
| National Grid | Central and Western MA (Worcester, Springfield, Lowell) | ~$0.32/kWh |
| Unitil | Fitchburg, Lunenburg, and surrounding towns | Market-based |
Credits roll forward monthly. At the end of each 12-month period, any remaining excess credits are typically paid out at a reduced “wholesale” rate. In practice, a properly sized system rarely accumulates large end-of-year surpluses — it’s more financially efficient to size for self-consumption than to overbuild.
Is Solar Worth It in Massachusetts?
Massachusetts is one of the strongest solar markets in the country, even after losing the federal ITC. Here’s the honest picture:
The case for solar in Massachusetts:
– Electricity rates: Massachusetts averages $0.3151/kWh, the second-highest in the nation (EIA, Q1 2026). Every kWh your system produces is worth nearly twice as much as in a low-rate state like Louisiana ($0.12/kWh).
– SMART income: No other state currently pays a guaranteed per-kWh production incentive for 20 years on top of net metering. It meaningfully reduces effective payback.
– Net metering: Full 1:1 retail-rate net metering remains intact with no active legislative threats as of May 2026.
– Panel warranties: Modern panels are warrantied for 25 years. An 8–9 year payback leaves 16+ years of essentially free electricity.
The case against — or for waiting:
– Shorter solar resource: Massachusetts gets 3.9–4.2 peak sun hours/day vs. 5.5–6+ hours in Arizona. A system that would cost $30,000 in Phoenix might need to be slightly oversized in Boston to produce the same annual output.
– Lost federal credit: Without the 30% ITC, Massachusetts paybacks are 1.5–2 years longer than they were in 2025.
– Older housing stock: Many Massachusetts homes need roof work before installation, adding $5,000–$15,000 to the effective cost.
Verdict: For a Massachusetts homeowner with a $150–$300/month electricity bill, a south- or west-facing roof with minimal shading, and plans to stay for at least 10 years, solar is financially sound. Run your own numbers with our solar cost calculator or compare the general ROI picture at Is solar worth it?.
Worked Examples: Real Numbers for MA Homeowners
These examples are calculated with location-specific inputs. System size formula: monthly bill ÷ electricity rate ÷ 30 days ÷ peak sun hours × 1.25 efficiency factor. Annual savings formula: monthly bill × 12 × 0.85 (solar offsets ~85% of usage via net metering). Annual SMART income: system kW × peak sun hours × 365 × 0.85 × $0.03/kWh.
| Location | Utility | Monthly Bill | Peak Sun Hrs/Day | System Size | Gross Cost | After Incentives† | Ann. Savings (Net Metering) | Ann. SMART Income | Payback |
|---|---|---|---|---|---|---|---|---|---|
| Boston | Eversource | $250 | 4.0 | 8.3 kW | $26,228 | $24,162 | $2,550 | $309 | 8.5 yrs |
| Worcester | National Grid | $175 | 3.9 | 6.0 kW | $18,960 | $17,190 | $1,785 | $218 | 8.6 yrs |
| Springfield | National Grid | $200 | 4.1 | 6.5 kW | $20,540 | $18,705 | $2,040 | $248 | 8.2 yrs |
| Cape Cod | Eversource | $300 | 4.2 | 9.5 kW | $30,020 | $27,800 | $3,060 | $371 | 8.1 yrs |
†After-incentive cost deducts MA state income tax credit ($1,000 cap) and 6.25% sales tax exemption on equipment (65% of total cost). Federal ITC not included (expired Dec. 31, 2025).
Peak sun hours by location: Boston 4.0 hrs/day, Worcester 3.9 hrs/day, Springfield 4.1 hrs/day, Cape Cod 4.2 hrs/day (NREL solar irradiance data). Electricity rate: $0.3151/kWh (EIA MA residential average, Q1 2026). Cost per watt: $3.16/watt (MA statewide installed average, 2026).
Top Solar Companies in Massachusetts
When choosing an installer, look for NABCEP-certified technicians, documented experience with the SMART 3.0 application process, and knowledge of your local utility’s interconnection timeline (Eversource interconnection approvals currently run 8–14 weeks). Always get at least three quotes — pricing for comparable systems can vary by $0.20–$0.40/watt, which is $4,000–$8,000 on a 10 kW system.
| Company | Best For | Service Area | Financing Options | Website |
|---|---|---|---|---|
| Boston Solar | SMART program expertise; local MA roots since 2011; 6,000+ installs | Eastern MA, southern NH | Cash, loan | bostonsolar.us |
| Sunrun | Lease/PPA for $0-down; national warranty backing | Statewide | Cash, loan, lease, PPA | sunrun.com |
| Trinity Solar | 30+ years regional experience; 124,000+ installations | Statewide | Cash, loan, lease | trinitysolar.com |
| My Generation Energy | Cape Cod and South Shore specialist; #1 Cape Cod installer (Solar Power World) | South Shore, Cape Cod, Islands | Cash, loan | mygenerationenergy.com |
For full company scores and head-to-head comparisons, see our best solar companies guide.
Lease vs. buy note: Leases and PPAs offered by Sunrun lock you into a payment for 20–25 years and the company, not you, owns the system and claims whatever tax credits are available. You won’t build equity. Buying — via cash or a solar loan — gives you full ownership, SMART program eligibility, and the property tax exemption.
How to Claim the Massachusetts Solar State Tax Credit
- Install your system on your primary Massachusetts residence using a licensed installer.
- Obtain all completion documents from your installer — Certificate of Completion, utility Permission to Operate letter, and your final invoice showing total system cost.
- Calculate your credit: multiply total system cost by 15%, then apply the $1,000 cap. (Example: $20,000 system × 15% = $3,000 → capped at $1,000.)
- File Schedule EC (Massachusetts Schedule EC, “Solar and Wind Energy Credit”) as part of your state income tax return (Form 1 or Form 1-NR/PY).
- Enter the credit amount on the appropriate line of Schedule EC, then carry the total to the credits section of your main return.
- Carry forward unused credit: If your Massachusetts tax liability is less than $1,000, carry any unused credit forward for up to three additional tax years.
Frequently Asked Questions
Does Massachusetts have a solar tax credit?
Yes. Massachusetts offers a 15% state income tax credit on the cost of a solar system installed on your primary residence, capped at $1,000. The credit is non-refundable and can be carried forward for up to three years if your tax liability is less than $1,000.
Is the federal 30% solar tax credit available in Massachusetts in 2026?
No. The federal Residential Clean Energy Credit (Section 25D) expired for new residential installations after December 31, 2025, under the One Big Beautiful Bill (signed July 4, 2025). If you installed solar in 2025, you can still claim the credit on your 2025 federal taxes. New 2026 installations do not qualify.
What is the SMART program and how much does it pay in 2026?
SMART (Solar Massachusetts Renewable Target) 3.0 pays residential solar owners a fixed $0.03 per kWh their system produces for 20 years, on top of net metering credits. Available through Eversource, National Grid, and Unitil. A 10 kW system earns approximately $372 per year — $7,440 over the 20-year term.
How long does solar payback take in Massachusetts?
Most Massachusetts homeowners see payback in 8–9 years without the federal ITC (which expired December 31, 2025). With the second-highest electricity rates in the nation ($0.3151/kWh), strong net metering credits, and SMART program income, the economics remain favorable despite the lost federal credit.
Will solar panels increase my property taxes in Massachusetts?
No. Massachusetts law mandates a 100% property tax exemption on the added value of a solar system for 20 years from the date of installation. You pay no additional property tax regardless of how much the solar panels add to your home’s assessed value.
Get Free Quotes →
Compare quotes from Massachusetts-licensed solar installers. Getting at least three quotes is the single most effective way to reduce what you pay — system pricing can vary by thousands of dollars for identical equipment.
Methodology and Sources
How we researched this guide: Cost-per-watt figures are drawn from EnergySage’s Massachusetts solar cost database and NuWatt Energy’s 2026 Massachusetts pricing analysis ($3.16/watt statewide average; $2.95–$3.40/watt range). Electricity rates use EIA Electric Power Monthly data (Q1 2026; Massachusetts residential average $0.3151/kWh). Peak sun hours per city are based on NREL solar irradiance data: Boston 4.0 hr/day, Worcester 3.9 hr/day, Springfield 4.1 hr/day, Cape Cod 4.2 hr/day. SMART 3.0 base rate ($0.03/kWh for 20 years) sourced from Mass.gov SMART 3.0 Program Details page. Net metering credit rates (Eversource ~$0.2836/kWh; National Grid ~$0.32/kWh) sourced from NuWatt Energy’s 2026 Massachusetts net metering guide. Federal ITC expiration confirmed via IRS.gov FAQs for modifications to Sections 25C and 25D under Public Law 119-21 (One Big Beautiful Bill, July 4, 2025). State tax credit and exemption details confirmed via EnergySage Massachusetts incentives data and Boston Solar resource center.
External sources:
– NREL Solar Data
– EIA Electricity Monthly Data
– Mass.gov — SMART 3.0 Program Details
– IRS.gov — FAQs for Section 25D modifications under OBBB
– EnergySage — Massachusetts Solar Data
– NuWatt Energy — Massachusetts Solar Cost 2026
Also see: National solar panel cost guide | Is solar worth it? | Federal solar tax credit guide | Best solar companies | Solar cost calculator