Is There a Window Tax Credit in 2026? What Changed (and What Still Helps)

What changed: the 25C credit ended December 31, 2025

The Energy Efficient Home Improvement Credit (Internal Revenue Code Section 25C) — the one worth up to $600 per year for qualifying exterior windows and skylights — was terminated by the tax law passed in July 2025 (Public Law 119-21). Per the IRS: the credit is not allowed for any property placed in service after December 31, 2025.

“Placed in service” means installed and ready for use — not ordered, not paid for, not sitting in the garage. There is no binding-contract exception for windows. If your windows went in on or after January 1, 2026, there is no federal credit to claim, no matter when you signed.

Who can still claim money

If your qualifying ENERGY STAR windows were installed by December 31, 2025 and you didn’t claim the credit, you’re not out of luck: the credit is claimed on your tax return for the year of installation (Form 5695), and amended returns are generally allowed within three years. Dig out the manufacturer certification and your itemized invoice, and talk to your tax preparer.

Projects that straddled the deadline count window by window — only units actually installed by December 31, 2025 qualify.

What still lowers the cost of a 2026 window project

Utility rebates: Pennsylvania utilities run efficiency programs that change year to year — check your electric utility’s current offerings before you buy.

Manufacturer and dealer promotions: with the federal credit gone, brands lean harder on seasonal discounts and financing promotions — they’re negotiable, especially with a competing quote in hand.

Right-sizing the project: a careful assessment often finds that only some windows need replacement now. And energy savings themselves haven’t gone anywhere: tight, Low-E replacement windows keep cutting heating bills every Pennsylvania winter, credit or no credit.

Don’t let a sales pitch invent a deadline

Expect to hear urgency built around tax season anyway. If a salesperson implies a federal window credit exists for 2026 installations, that’s your cue about how the rest of the pitch is calibrated.

The honest math for 2026 is simpler: the best price comes from an itemized quote from a vetted local contractor, compared fairly against any competing offer. Our free matching service will set that up — one local pro, one written quote, no pressure and no imaginary deadlines.