Installed solar in 2025? How the date test, Form 5695 and the carryforward work

Three wordings for one cutoff, and which one governs

Start with the law, because the other two texts are the IRS describing it. Section 25D of the Internal Revenue Code was amended by Public Law 119-21, section 70506, signed July 4, 2025. Subsection (h) now reads that the credit "shall not apply with respect to any expenditures made after December 31, 2025." The word that does the work is made, and subsection (e)(8) defines it: an expenditure on an item "shall be treated as made when the original installation of the item is completed." A second rule covers building a home: an expenditure connected with construction is treated as made when the taxpayer's original use of the constructed structure begins.

The 2025 Form 5695 instructions, the version dated January 22, 2026, repeat the statute almost word for word. Their "What's New" box says you cannot claim residential clean energy credits for expenditures made after December 31, 2025, and the "Costs" paragraph says costs are treated as paid when the original installation of the item is completed, or, for a home you built, when your original use of the constructed home begins. The IRS answer on the 2025 law change (Fact Sheet 2025-05, August 21, 2025, question 7) puts the borderline case in plain terms: asked whether a credit is available for property installed after December 31, 2025 if payment was made by that date, it answers no, because of the same installation-completion rule.

The IRS credit page, last reviewed July 4, 2026, uses a different phrase: the credit "is not available for any property placed in service after December 31, 2025." That sentence is the one most articles quote, which is why "placed in service" has become the shorthand for this deadline. The statute for this credit does not use it. The distinction would be academic if the two events always fell on the same day, but a solar system can be physically finished on one date and switched on by the utility on another, so the wording is worth separating.

Where wordings differ, the statute controls, and the IRS says so about its own FAQs: if an FAQ turns out to be an inaccurate statement of the law as applied to a taxpayer's case, the law controls. That is why this page treats installation completion as the working test and treats the placed-in-service phrasing as the IRS's shorthand for the same thing.

One caution about older pages. IRS Fact Sheet 2025-01, updated January 17, 2025, still describes the credit as running through 2034 with a phase-down. That is the schedule Public Law 119-21 replaced. The same fact sheet is still the right place to read the mechanics that did not change, such as what counts as a cost, and it is cited below for those, never for a date.

Why the commercial-credit rules do not rescue a late install

A common assumption is that a homeowner can preserve the credit the way a business solar project can, by starting construction before a cutoff. That idea has no footing here, and the Form 5695 instructions say so directly. They carry a caution that IRS guidance issued for the energy credit under section 48, naming Notice 2018-59 and Notice 2021-41, does not apply to the residential energy credits. Those two notices are the begin-construction and continuity guidance that business solar developers rely on.

In practice that closes three escape routes. Begin-construction tests do not apply to a homeowner's credit, so a signed contract preserves nothing. A deposit or a prepaid invoice is not an expenditure made, because the expenditure is treated as made at completion of installation. And equipment bought and stored in 2025 for a roof job scheduled for early 2026 does not carry the credit with it. The credit status page states the same position from the legal side; this page is about the paperwork once the facts fall on the right side of the date.

What no IRS text we read says about permission to operate

The question that matters most to people with a December installation is whether the utility's permission to operate, the step that lets the system export, moves the date. None of the texts in the table above mentions permission to operate, interconnection approval or a utility inspection. They key to installation. The statute does not define "original installation of the item is completed," and we found no IRS document that defines it for solar.

That leaves a gap, and the honest way to describe it is as a gap. If the crew finished mounting, wiring and commissioning in December and the system sat idle for weeks waiting for the utility, the plain text points to December, since nothing in the text ties completion to a utility step. Against that, a preparer or the IRS could read completion to include a passed final inspection, because a system that cannot lawfully be energized is arguably not yet an installed system. We found no source that resolves it either way.

The practical response is documentary, not argumentative. Collect dates for each event so the file shows the whole sequence: the day the crew finished, the day the local building authority signed off, the day the utility granted permission, and the day the system first produced power. The installation process guide names the stage at which each of those documents is created. If all four fall in 2025, the question never arises. If they straddle December 31, raise it with whoever prepares your return before filing.

Eight dated cases against the rule

The table below applies the statute, the instructions and FAQ 7 to situations that come up around the year-end deadline. The dates are invented for illustration; the answers are what the cited texts say, and where a case is our reading rather than a quoted rule, the table says so.

Three of these deserve a closer look because the intuitive answer is wrong. The first is the paid-in-full case. A homeowner who prepaid in December 2025 to lock a price might reasonably assume the payment date matters. FAQ 7 addresses exactly that assumption, and the answer is that it does not. The money can go out in 2025 and the credit can still be gone.

The second is the new-build case. A person who contracted for a house with a solar roof, watched the panels go up in autumn 2025 and closed in January 2026 has an expenditure that is treated as made on the day original use begins. The instructions say this in so many words for the residential clean energy credit, and note that Part I applies to homes being constructed as well as existing ones. Builders and buyers should check the move-in date against December 31 before assuming anything.

The third is the add-on battery. Because the statute speaks of an expenditure on an item, and because a battery is listed in the form on its own line, we read a battery as a separate item with its own completion date. If a battery was installed with the panels in a single project and finished the same day, there is nothing to separate. If it was added after the new year, it falls outside even when the panels fell inside. The battery retrofit guide covers the permit and tariff side of adding storage later.

The lease row is short on purpose. Part I asks for amounts you paid for qualified property, and a monthly lease charge to a company that owns the system is not that. How the leasing company is treated is a different tax question, covered in the lease and PPA guides rather than here; see lease, buy or PPA for the ownership comparison.

Which costs go on the lines, and which do not

Once the date is settled, the next mistake is the amount. The form asks for what you paid for qualified property and, per the instructions, the labor "properly allocable to the onsite preparation, assembly, or original installation" plus the piping or wiring needed to interconnect the property to the home. In a solar quote, that means the panels, inverters, racking, the installation labor, and the wiring from the array to the home. Your installer's itemized final invoice is the source document, not the sales brochure.

Subsidies deserve their own paragraph because they are where an honest filer can overstate the base. Fact Sheet 2025-01 draws three lines. A subsidy a public utility pays for the purchase or installation, if it was not included in your gross income, must be subtracted from the cost before you figure the credit, whether you or your contractor received it. A rebate that reduces the purchase price, from someone with a reasonable connection to the sale, is subtracted as well. A state energy incentive generally is not subtracted unless it qualifies as a rebate under federal income tax law, and the IRS warns that many programs labeled rebates may not, and may even be taxable. Net metering credits for exported electricity are not subsidies for installing the property and do not change the credit.

Our rule of thumb for a utility or state payment is to ask what it is and to read the program's own tax language before choosing a line. If a program says it is taxable income, or calls itself a performance payment for energy produced, it points away from a cost reduction. If it is described as a price reduction on equipment, it points toward one. The state credits table notes where a state credit's own formula starts from a net figure.

Part I of the 2025 form, line by line

The 2025 form is a single page for this credit. The lines below are quoted from the form revision created March 20, 2025 and the instructions dated January 22, 2026, both fetched October 23, 2026. The right-hand column carries a filing illustration: an 8 kW system priced at this site's comparison line of $2.95 per watt DC ($23,600; the U.S. Department of Energy's Q1 2025 residential benchmark, modeled market price for an 8 kW system in 2024 dollars, checked October 30, 2026), with no battery, a taxpayer whose Form 1040 line 18 amount is $5,200 and whose other listed credits on the worksheet total $2,000. These inputs are assumptions for the arithmetic. They are not a price survey and not a forecast of what any household will owe.

The only line that needs real work is 14, and it is a subtraction. The instructions' worksheet starts from the amount on Form 1040 line 18, then subtracts the other credits you are taking that year: among them the foreign tax credit, the child and dependent care credit, education credits, the retirement savings credit, the energy efficient home improvement credit from Form 5695 line 32, the clean vehicle credits, the child tax credit, the mortgage interest credit and the adoption credit. Whatever remains is the most the clean energy credit can reduce. In the illustration, $5,200 less $2,000 leaves $3,200, so line 15 is $3,200 although line 13 is $7,080.

Two features of the form are easy to miss. First, the note at the top of Part I lets you skip lines 1 through 11 if you only have a carryforward from 2024, and line 12 pulls that amount from your 2024 form. A household that installed solar in 2024 and carried part of the credit forward is filling in line 12, not line 1. Second, the instructions ask you to file the form even if you cannot use any of the credit in 2025, because line 16 is how the unused balance is recorded for the following year.

With a battery the arithmetic extends in one place. If the same household had added a 13.5 kWh battery in the same project, finished before the cutoff, line 5a would be Yes and line 5b would carry its cost. The DOE residential benchmark gap between a PV-only and a PV-plus-storage system, our arithmetic on its Q1 2025 figures, is about $13,120 for an 8 kW system with a 13.5 kWh battery. Adding that to line 6a would raise line 13 by $3,936 at 30 percent, and under this illustration's $3,200 limit nothing in 2025 would change, only the carryforward would grow.

The file that proves your date

Neither the form nor its instructions lists documents to keep, so what follows is the file we would assemble, not an IRS requirement. The aim is that if anyone ever asks when the original installation was completed and what you paid, the answer is a stack of dated papers rather than recollection.

Start with the itemized final invoice that separates equipment, labor and any non-qualifying work such as re-roofing. If the invoice is a single lump sum, ask the installer for a line-item breakdown now, because splitting a lump sum years later is much harder. Keep proof of payment, which supports the amount rather than the date. Keep the installer's completion statement or commissioning record, which comes closest to the statutory event. Keep the final inspection sign-off from your building department, and the utility's permission-to-operate notice, even though no IRS text names either, because together they show the whole sequence.

For a battery, keep the specification sheet showing usable capacity, since line 5a turns on whether capacity is at least 3 kilowatt hours. For any utility or state payment, keep the program letter that says how it is characterized. And keep a copy of the filed Form 5695, since the 2026 form will ask for its line 16.

Missed it on the original return

If a 2025 installation never made it onto a filed return, the credit is not lost by that alone. Fact Sheet 2025-01 answers that a taxpayer who did not claim the credit can amend, and says that to claim a refund an amended return generally must be filed within 3 years after the original return was filed or 2 years after the tax was paid, whichever is later. The same fact sheet adds that the credit is allowed for the tax year in which the expenditure is incurred, so a 2025 installation belongs on the 2025 return and cannot be moved to a different year to suit your tax bill.

Two limits keep that from being a rescue for a late install. An amended return corrects the claim for the right year; it cannot convert a 2026 completion into a 2025 one. And the amount the credit can offset is still capped by that year's liability, so an amended return for a low-tax year may produce a carryforward, not a refund.

What the credit does to your home's basis

The statute's subsection (f) and the Form 5695 instructions say the same thing: if the credit is allowed, the increase in your home's basis from the expenditure is reduced by the amount of the credit. Basis is your cost for tax purposes, and it matters when you sell. A solar system you own normally adds its cost to the home's basis. With the credit claimed, the addition is the cost minus the credit.

In the illustration above the system cost $23,600. The credit allowed in 2025 is $3,200, and as the carryforward is later used, the allowed credit rises. The basis increase is the cost minus the credit allowed, so on the first-year numbers alone the increase would be $20,400, and once the whole $7,080 has been used it would be $16,520. Whether that matters at sale depends on your gain and on exclusions that are outside this page. The move-or-sell page covers how a system affects a sale, and a tax preparer should handle the basis record itself.

A carryforward followed year by year

The credit is nonrefundable, meaning it can reduce tax to zero but never produce a refund beyond it, and the statute's subsection (c) carries any excess to the succeeding taxable year. The text of that subsection contains no end year, and IRS Fact Sheet 2025-01 says an unused amount may be carried forward to reduce tax liability in future taxable years. The termination in subsection (h) is aimed at expenditures made, and as we read it does not reach a balance already earned, which fits why the 2026 form is built around carrying 2025's balance forward.

That 2026 form is currently a draft. The IRS early-release draft of Form 5695 for 2026, created April 1, 2026, is a four-line form titled Carryforward of Residential Energy Credit: line 1 is the carryforward from your 2025 Form 5695 line 16, line 2 is the tax-liability limit from a worksheet, line 3 is the smaller of the two and goes to Schedule 3 line 5a, and line 4 is the carryforward to 2027. The draft instructions, dated August 27, 2026, add a caution that you may claim only a carryforward of unused credit shown on the prior-year line 16, and still say to file the form even in a year when none can be used. A draft can change before release, and no 2027 form exists yet, so the 2027 row below rests on the statute and on the pattern of the 2026 draft.

The table follows the illustration through three tax years. Every tax and credit input is assumed and printed; real households will have different numbers, and tax law for 2026 and 2027 may change. The worksheet logic is the one the instructions print: tax from Form 1040 line 18, minus other listed credits, equals the most the credit can reduce.

Two things change the shape of that table in real life. A household with a very small liability uses little each year, and a balance can stretch across many returns, which is where the absence of an end year in the statute matters. And a household whose tax rises, for instance from a raise, a sale of an investment or a retirement distribution, can use the whole balance in one year. Because the credit is applied after the other listed credits, using it up faster does not change its total; it changes only when the benefit arrives.

The practical routine is short. Each year until the balance is zero, keep the prior-year Form 5695, copy its line 16 or line 4 forward to the new form's first line, complete the limit worksheet from that year's return, and file even when the limit is zero. If you sell the house while a balance remains, a preparer will need the form history to decide what, if anything, can still be used; this page does not address that situation.