How to Claim the Window Tax Credit: Form 5695

If you installed qualifying energy-efficient windows in 2025, you claim the credit on IRS Form 5695, Residential Energy Credits, Part II, lines 20a through 20d. The credit equals 30% of the product cost, capped at $600 for all windows and skylights combined, and it reduces your federal income tax when you file your 2025 return in 2026. One warning up front: the Energy Efficient Home Improvement Credit under Section 25C expired on December 31, 2025, so windows placed in service on or after January 1, 2026 do not qualify.¹

Do Your Windows Still Qualify

The credit year follows installation, not purchase. Windows bought in 2025 but not installed and operational until January 2026 miss the cutoff. If installation finished by December 31, 2025, you claim the credit on the return for the year installation was completed.²

The property itself has to fit a narrow definition. Windows must go into an existing home that you own and use as your primary residence. New construction does not qualify. Rental properties do not qualify. A second home or vacation home does not qualify for the window credit specifically, even though some other 25C improvements like heat pumps have looser residence rules.³

The windows themselves must meet the ENERGY STAR Most Efficient standard. Ordinary ENERGY STAR certification is not enough. The Most Efficient designation applies specific U-factor and Solar Heat Gain Coefficient thresholds that vary by climate zone.⁴

There is one more requirement that applies only to 2025 installations. Each qualifying window must have been produced by a qualified manufacturer, and you must report the Qualified Manufacturer Identification Number (QMID) for each window on your return. Without a QMID, the IRS will deny the credit. The number is on the product label or in the manufacturer’s documentation; if you cannot find it, contact the retailer or manufacturer before you file.²

How Much the Credit Is Worth

The credit equals 30% of what you paid for the windows themselves. Installation labor, delivery, and site prep do not count.⁵ The credit for all exterior windows and skylights combined is capped at $600 per year. If you spent $3,000 on qualifying windows, 30% is $900, but your credit stops at $600. If you spent $1,500, 30% is $450, and that is your credit.⁶

That $600 window cap sits inside a broader $1,200 annual limit for building-envelope improvements, which also covers doors (up to $250 per door, $500 total), insulation, and home energy audits ($150 maximum). If you replaced windows and doors in the same year, the combined credits from those items cannot push past $1,200.⁶

Two features of the credit trip people up. It is non-refundable, so it can zero out your federal tax but cannot generate a refund larger than what you already paid in. And unused credit does not carry forward to future years. If your tax liability for 2025 is $400 and your window credit is $600, the extra $200 is gone.⁷ With the credit expired, there is no future year to save it for.

Filling Out Form 5695

Windows and skylights go in Part II of Form 5695, lines 20a through 20d. Line 19 is for exterior doors, not windows, so do not put your window costs there.⁵

Line 20a: enter the QMID and cost for your four most expensive qualifying windows or skylights.
Line 20b: enter the total cost for any remaining qualifying windows and skylights. If you use this line, attach a statement listing the QMID and cost for each additional item.
Line 20d: your total window and skylight credit. Do not enter more than $600.⁵

The form applies the 30% rate to your product costs, caps the window figure at $600, and combines it with any other Part II credits you qualify for. The Part II total then flows onto your Form 1040 and reduces your tax for the year.⁸

File Form 5695 with your standard Form 1040. Tax software integrates it automatically. Paper filers attach it to the return before mailing.⁹

Documents to Keep

You do not submit supporting paperwork with your return, but you need it available if the IRS asks. Hold on to:

The manufacturer’s certification statement confirming the windows meet ENERGY STAR Most Efficient requirements. This is usually available on the manufacturer’s website or from your retailer.⁵
The ENERGY STAR labels from the windows themselves, showing model numbers and efficiency ratings.
Itemized purchase receipts that separate product cost from installation labor, since only the product cost qualifies.
QMID information for each window installed in 2025.

Keep everything for at least three years after filing the return that claims the credit. That matches the standard IRS audit window for most taxpayers.¹⁰

1
Internal Revenue Service. FAQs for Modification of Sections 25C, 25D, 25E, 30C, 30D, 45L, 45W, and 179D Under Public Law 119-21
2
Internal Revenue Service. Energy Efficient Home Improvement Credit
3
Internal Revenue Service. Frequently Asked Questions About Energy Efficient Home Improvements and Residential Clean Energy Property Credits – Energy Efficient Home Improvement Credit – Qualifying Residence
4
ENERGY STAR. Windows and Skylights Tax Credit
5
Internal Revenue Service. Instructions for Form 5695 (2025)
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Office of the Law Revision Counsel. 26 USC 25C – Energy Efficient Home Improvement Credit
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Internal Revenue Service. Frequently Asked Questions About Energy Efficient Home Improvements and Residential Clean Energy Property Credits – Energy Efficient Home Improvement Credit – Timing of Credits
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Internal Revenue Service. About Form 5695, Residential Energy Credits
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Internal Revenue Service. How to Claim a Residential Clean Energy Tax Credit
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Internal Revenue Service. How Long Should I Keep Records