Federal Solar Tax Credit Calculator

Why a system installed today gets nothing federal

For homeowners, this is the single most important fact on this page, and it is easy to miss because so much online content was written before it took effect. The IRS's own Residential Clean Energy Credit page states: "The Residential Clean Energy Credit equals 30% of the costs of new, qualified clean energy property for your home installed anytime from 2022 through December 31, 2025. The credit is not available for any property placed in service after December 31, 2025." That is not a phase-down. It is a hard stop. A system placed in service on January 1, 2026 or later gets a federal credit of exactly $0, no matter how it was quoted or financed.

Qualified expenses under the credit, while it applied, covered solar electric panels, solar water heaters, wind turbines, geothermal heat pumps, fuel cells, and battery storage of at least 3 kWh (from 2023 onward), along with the onsite labor to prep, assemble, and originally install the system and connect its piping or wiring. Solar roofing tiles and shingles qualified as the solar property itself; a traditional asphalt roof or the trusses supporting the array did not, because they are not clean-energy property in their own right.

How this calculator computes the credit — for systems that still qualify

Two inputs drive the whole calculation: your total system cost and any utility rebate you received. The rebate matters because it reduces the cost basis the credit is calculated against — a utility rebate is treated as lowering what you actually paid, while most state tax credits are not subtracted this way.

That $8,400 gap is why this calculator forces you to pick an install year rather than assuming one. Every dollar of it disappeared for anyone placing a residential system in service after December 31, 2025, regardless of when the contract was signed or the deposit paid — the statute keys off the in-service date, not the purchase date.

Two different credits: don't let a quote blur them

Section 25D and Section 48E are both 30% credits and both live under the umbrella term "the solar tax credit," which is exactly how homeowners get misled by an installer's marketing sheet or a stale blog post. Section 25D is the residential credit this page has been describing, and it expired for property placed in service after December 31, 2025. Section 48E is the commercial investment tax credit for business, rental, and commercial solar projects, and it remains active at the full 30% rate — projects above 1 MW must additionally meet prevailing wage and apprenticeship requirements to earn that full rate, but smaller commercial systems typically qualify without them.

If a system is going on a primary residence, only §25D ever applied, and it is closed. If the same array is going on a rental property held as a business, financed by an LLC, or installed for a commercial building, §48E may still apply — that determination turns on how the property is held, not on the panels themselves, and it is worth confirming with a tax professional before assuming either way.

Claiming the credit and what happens to what's left over

Residential filers who qualified — systems placed in service through 2025 — claim the credit on IRS Form 5695 with the federal return for that tax year. Commercial filers claiming §48E generally use Form 3468 instead. Both credits are nonrefundable: they reduce tax liability but cannot generate a refund by themselves. If the credit is larger than what you owe in the year you claim it, the unused portion generally carries forward to future tax years rather than being lost.

The IRS page carries one loose end worth flagging rather than resolving: alongside the December 31, 2025 cutoff, it also retains an older sentence referencing a phase-out in 2033 that applied under a prior version of the credit. The 2025 cutoff is the current, operative rule for the residential credit — this calculator and this page follow it, and the leftover 2033 language should not be read as reviving the credit.

What counted as qualified property while the credit was open

The list of qualified property matters even now, because it determines what a homeowner who installed before the cutoff was actually entitled to claim, and what an auditor or amended return would still measure against. Qualified expenses covered solar electric panels, solar water heaters, wind turbines, geothermal heat pumps, fuel cells, and battery storage of at least 3 kWh (added as an eligible category starting in 2023), plus the onsite labor for preparation, assembly, and original installation and the cost of connecting piping or wiring. Used, previously-installed property never qualified — only new equipment did.

There was no annual or lifetime dollar cap on the credit for solar, geothermal, wind, or qualifying battery storage — a larger system simply earned a larger 30% credit with no ceiling. The one exception was fuel cells, which the IRS capped at $500 per half kilowatt of capacity, or $1,667 per half kilowatt for a jointly-occupied household splitting the credit. That fuel-cell cap is a narrow exception worth knowing if a system combined solar with fuel-cell backup, since the two components were not treated identically even under the same credit.

Roofing materials sat on the boundary the IRS drew explicitly: solar roofing tiles and solar shingles qualified because they are themselves the solar-electric property, generating power as part of the roof surface. Traditional asphalt shingles and the roof trusses or decking that merely support a bolted-on panel array did not qualify, even on the same job, because they perform a structural or weatherproofing role rather than an energy-generating one.