Incentives & Rebates
Understanding Hawaii's solar panel tax credits
Hawaii offers a state tax credit for residential solar on top of the federal solar tax credit, and together they can meaningfully reduce the cost of going solar. Here is how each one works and how to claim them.
If you are weighing the cost of installing solar panels on your Hawaii home, tax credits are one of the biggest levers available to bring that cost down. Two credits typically apply: a Hawaii state tax credit and a federal tax credit, and understanding how each works helps you plan an installation and a tax filing that captures the full benefit.
Tax credit versus tax deduction
It helps to start with the distinction. A tax deduction reduces the income you are taxed on. A tax credit reduces the tax you owe, dollar for dollar. Solar incentives in Hawaii are structured as credits, which makes them a direct, and often substantial, reduction in what a system actually costs you out of pocket.
The Hawaii state solar tax credit
Hawaii offers a state tax credit for residential solar energy system costs, historically set at 35% of the cost of installing solar panels on your home, up to state-set caps. On a $10,000 installation, a 35% credit would reduce your effective state tax liability by $3,500. This credit is claimed using Form N-342, the Hawaii Renewable Energy Technologies Income Tax Credit form, filed with your state return.
Because the exact caps and rules can be adjusted by the state legislature over time, it is worth confirming the current terms with a tax professional or the Hawaii Department of Taxation before you file, rather than relying on a number from a prior tax year.
The federal solar tax credit
The federal Residential Clean Energy Credit works the same way at the federal level: it applies a percentage credit to the total cost of your solar installation, claimed using IRS Form 5695 with your federal return. The percentage and expiration date for this credit have changed multiple times as Congress has extended and adjusted it, so the rate that applies to your system depends on when it is placed in service. Our post on the federal solar tax credit deadline covers the most current federal timeline in detail, since this is the credit most likely to change from year to year.
How to claim both credits
- Gather documentation. Keep every invoice, contract, and receipt related to your solar installation. You will need proof of both the cost and the date the system was placed in service.
- Confirm eligibility. A tax professional can confirm which tax year your installation falls into and which credit percentages apply.
- File Form N-342 with your Hawaii state return to claim the state credit.
- File Form 5695 with your federal return to claim the federal credit.
- Keep your records. Retain your paperwork in case of an audit; both state and federal tax authorities can request documentation well after the credit is claimed.
Why professional guidance matters here
Solar tax credit rules change. Percentages, caps, and expiration dates have moved multiple times over the past decade at both the state and federal level, and what applied to a system installed a few years ago is not necessarily what applies today. A CPA or tax preparer familiar with renewable energy credits is the right resource to confirm exact numbers for your specific installation date and household situation. Our team can provide the documentation you need, but we are not a substitute for tax advice on your specific return.
Tax credits are only part of the incentive picture
State and federal tax credits stack with other Hawaii-specific incentives you may qualify for, including Hawaiian Electric programs related to battery storage and grid services. If you are also considering a solar battery alongside your panels, it is worth reviewing our overview of Hawaii solar incentives so you can plan your installation to capture every credit and rebate you are eligible for in the same tax year.
The bottom line
Between the Hawaii state credit and the federal credit, a well-timed solar installation can see a meaningful share of its total cost offset through tax credits alone, on top of the ongoing savings from lower electric bills. Because rates and rules shift, the two things worth doing before you sign a contract are: confirm current credit percentages with a tax professional, and get an installation timeline that puts your system in service inside the tax year you are planning around.
Get a free estimate from Independent Energy Hawaii, and we will walk you through the documentation you will need to bring to your tax professional.
Hawaii state solar tax credit
Going solar in 2026 locks in your full state tax credit. Waiting until 2027 does not.
Under Act 24, the Hawaii state solar tax credit (RETITC) gets a hard $40 million statewide cap starting in 2027 and phases out entirely after 2029. Only systems placed in service (installed, inspected and operational) by December 31, 2026 are protected from that cap by Governor Green's executive order. A signed contract alone does not qualify.
Signing in 2026 is not enough. Signing a contract in 2026 does not qualify. Your system has to be installed, inspected and switched on (placed in service) by December 31, 2026.
Placed in service in 2026
Full credit protectedUp to $5,000
35% of system cost, capped at $5,000 per 5kW system
- System must be installed, inspected and operational by December 31, 2026, a signed contract is not enough
- Not subject to the $40M statewide cap, so your credit is not shared or reduced
- You know your credit up front, at signing
- No certification lottery to wait on
- Income limits may still apply, so higher earners should confirm
Install in 2027
Capped and uncertain~$2,000 to $3,000
Estimated. The actual amount depends on statewide demand.
- $40M statewide cap, split across all claims
- Households over $175K income no longer qualify
- You will not know your credit until the following spring
- Residential competes with commercial for the same pool
A typical residential customer could see a swing of $2,000 to $3,000 between installing in 2026 versus 2027.
Why the 2027 number is an estimate, not a promise
Starting in 2027 the state pays out a fixed $40 million per year, no matter how many people claim it. If total claims exceed the cap, every credit is reduced proportionally. Recent years have run near $100 million in claims, so here is how the math could land.
| If statewide claims total | The $40M cap covers | Your $5,000 credit becomes |
|---|---|---|
| $40M (demand drops to the cap) | 100% | $5,000 |
| $65M | ~62% | ~$3,100 |
| $100M (recent average) | ~40% | ~$2,000 |
| $130M (pre-sunset rush) | ~31% | ~$1,550 |
Income note: the Governor's executive order shielded 2026 installs from the $40M cap, but stated it did not cover the income limits. Households over $175K (single) or $350K (joint) should confirm 2026 eligibility with a tax advisor before counting on the credit.
Frequently Asked Questions
Do I need to itemize my taxes to claim the solar tax credit?
Can I claim the tax credit if I lease my solar system instead of buying it?
Does adding a battery qualify for the same tax credits as solar panels?
What happens if my tax credit is larger than what I owe in taxes that year?
When should I expect to receive the credit?
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