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Federal incentives
Federal Residential Clean Energy Credit (25D)
30% for systems installed 2022–2025; not available for installations completed after December 31, 2025[1]
The 30% federal credit for homeowners who bought solar ended with Public Law 119-21. A system counts in the year its installation is completed, so paying in 2025 for a 2026 installation does not qualify.
- Who
- Homeowners who bought and installed a system by December 31, 2025 claim it on IRS Form 5695 for that tax year.
- Deadline
- December 31, 2025
- Checked
- November 5, 2026
Business credit for leased and PPA systems (48E)
Claimed by the system owner, not the homeowner; solar must begin construction by July 4, 2026 or be in service by December 31, 2027[2]
If a company owns the panels on your roof (a lease or power purchase agreement), that company may claim the business clean electricity investment credit and can reflect it in your price. You cannot claim it yourself.
- Who
- Third-party-owned systems (leases and PPAs). Ask the provider whether the price assumes this credit.
- Deadline
- December 31, 2027
- Checked
- November 5, 2026
State incentives in Maine
Solar Energy Equipment Property Tax Exemption
Solar equipment that generates heat or electricity is exempt from local property tax (100% of the equipment's value); owner must file a report with the assessor by April 1 of the first year claimed[3]
For tax years from April 1, 2025: solar equipment whose energy is all used on site, or that is collocated with net energy billing customers subscribed to at least 50% of its output (rooftop home systems qualify).
- Who
- For tax years from April 1, 2025: solar equipment whose energy is all used on site, or that is collocated with net energy billing customers subscribed to at least 50% of its output (rooftop home systems qualify).
- Deadline
- None set in the source
- Checked
- November 5, 2026
How these incentives stack
Cash rebates are paid first and usually reduce the cost a tax credit is based on. State tax credits only help if you owe enough state income tax. Exemptions (sales and property tax) apply automatically or through a form, and they do not reduce what you owe the installer on paper, so check that a quote does not charge tax that the law exempts. The calculator applies the programs it can model and lets you switch utility rebates on or off.
FAQ
Frequently asked questions
Does Maine have a solar tax credit?
No. Maine offers exemptions and utility programs instead of a state income tax credit; see the list above.
Can I still get the federal solar tax credit?
No, not if you buy the system and installation is completed after December 31, 2025 (Federal Residential Clean Energy Credit (25D)[1]). If a company leases you the panels or sells you the power, that company may still claim a business credit and may pass some value on through the price.
sources
[ 3 ]Every number on this page links to one of these sources. Dates show when we last checked each one.
- IRS FS-2025-05: FAQs for modification of sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D under Public Law 119-21 (OBBB)irs.gov · checked Nov 5, 2026
- Public Law 119-21 - Sec. 70513(a) and (g)(5) (48E); Sec. 70512(a) and (l)(4) (45Y)govinfo.gov · checked Nov 5, 2026
- Maine Revised Statutes Title 36, Section 656(1)(L) - Property tax exemptions (solar energy equipment)legislature.maine.gov · checked Nov 5, 2026
Incentive list last re-checked November 5, 2026. Programs change; confirm with the program before you sign.
Change log
- Monthly output per kW in Portland updated to [80.5, 94.2, 124.0, 126.6, 141.2, 137.4, 141.4, 132.9, 120.5, 90.5, 67.9, 61.6] kWh/kW/month (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).
- Average solar radiation on the panels in Portland updated to 4.55 kWh/m2/day (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).
- Solar output per kW in Maine (PVWatts, Portland) updated to 1318.6 kWh/kW/yr (NREL/NLR PVWatts v8 (1 kW-DC, fixed roof mount, 20° tilt, south-facing, 14% losses, TMY weather)).
- Solar Energy Equipment Property Tax Exemption: now "Solar equipment that generates heat or electricity is exempt from local property tax (100% of the equipment's value); owner must file a report with the assessor by April 1 of the first year claimed" (active).
- What the rule says updated to “Generated kWh will be applied against the kWh that you have consumed during the billing cycle. This will reduce the amount of energy that you buy from your electric supplier” (Central Maine Power - Frequently Asked Net Energy Billing Questions (read via Wayback Machine copy of 15 Jul 2026)).