Pricing reviewed October 2026
Replacing a single-pane window with a double-pane unit costs about $550 to $1,100 per window for a standard double-hung, with a national average of $896 installed, according to Modernize (updated Aug 13, 2026). This Old House's 2026 survey of 1,000 window buyers found double-pane windows averaged $529 versus $400 for single-pane (This Old House, updated Aug 11, 2026). The U.S. Department of Energy estimates ENERGY STAR windows save 7%–15% on household energy bills, or roughly $71–$501 a year (DOE, Oct 2010).
Single-pane glass is still common in older homes, and the question most owners have is not "what does a window cost" but "is it worth tearing out windows that still open and close?" This guide puts the upgrade cost, the realistic savings and the payback math side by side, using only figures we could trace to a published source.
Single-pane to double-pane: cost at a glance
| Item | Typical cost | Source |
|---|---|---|
| Double-pane replacement window, installed (standard double-hung) | $550 – $1,100 (avg. $896) | Modernize, Aug 13, 2026 |
| Installation labor alone | $70 – $150 per window | Modernize, Aug 13, 2026 |
| Average paid, double-pane window (survey) | $529 | This Old House 2026 survey |
| Average paid, single-pane window (survey) | $400 | This Old House 2026 survey |
| Average paid, triple-pane window (survey) | $609 | This Old House 2026 survey |
| Window replacement, any glazing, per window | $300 – $2,500 (avg. $750) | Angi, Oct 15, 2026 |
Why the spread? Modernize quotes an installed price for a standard double-hung. This Old House reports what surveyed homeowners actually paid across styles and sizes, so its averages run lower. Treat Modernize's range as a typical quote and the survey numbers as a reality check.
What you get for the extra pane
A double-pane window seals two layers of glass around a spacer, usually with argon or another gas in the gap. Modernize notes the trapped gas "does the brunt of the insulating," and recommends "warm edge" spacers. Practical differences homeowners notice:
- Less condensation and frost on the inside glass in cold weather, because the inner pane stays closer to room temperature.
- Fewer drafts and better comfort near windows.
- Less outside noise.
Modernize adds a caveat worth heeding: keeping "even a couple of single paned windows" limits overall savings, so the upgrade pays best when you replace them all at once.
Energy savings and payback
The DOE's Guide to Energy-Efficient Windows says upgrading to ENERGY STAR windows can save 7%–15% on annual household energy bills, roughly $71–$501 a year "depending on your geographic location and the type of window being replaced." Single-pane replacements sit at the high end of that range because they start from the worst performance. The DOE also advises insulating and air-sealing the house before replacing windows.
This Old House's 2026 survey gives a real-world check: 36% of homeowners with new double-pane windows reported lower monthly energy bills, and among those who saw savings, $25–$49 a month (about $300–$588 a year) was the most common range.
Simple payback, worked out
Payback = cost of the upgrade ÷ yearly savings. Using only the sourced figures above, for one window:
| Scenario | Cost per window | Whole-house savings/yr | Payback depends on window count |
|---|---|---|---|
| Typical quote (Modernize avg.) | $896 | $71 – $501 (DOE) | 10 windows ≈ $8,960 ÷ $501 = about 18 years at the top of DOE's range |
| Survey average (This Old House) | $529 | $300 – $588 (survey, those who saw savings) | 10 windows ≈ $5,290 ÷ $588 = about 9 years |
These are our own arithmetic on the cited figures, not a forecast. Your payback will be shorter in a cold climate with expensive heating and longer in a mild climate. Comfort, condensation and noise improvements don't appear in the math but are often why people do it.
Tax credits in 2026
The federal Energy Efficient Home Improvement Credit capped exterior windows and skylights at $600 a year, but the IRS states it applies to improvements made "through December 31, 2025" (IRS, accessed Oct 29, 2026). Windows installed in 2026 should not be budgeted around that credit. Check your state energy office and utility for local rebates.
Alternatives if replacement doesn't pencil out
- Repair and weatherstrip: This Old House recommends repair or weatherstripping when windows "still work well."
- Replace the worst windows first: north-facing and draftiest windows give the most comfort per dollar, though Modernize notes partial upgrades limit total savings.
- Historic homes: some historic districts restrict window changes; This Old House flags added requirements there.
Choosing the frame
Frame material moves price more than pane count. In This Old House's survey vinyl averaged $472 and fiberglass $564 per window. See window cost by frame material for full ranges, and whole-house window replacement cost if you are doing every window at once.
Get a number for your exact windows with the window replacement cost calculator.
Check a contractor's license (HomeProFax)
Frequently asked questions
How much does it cost to replace a single-pane window with double-pane?
Modernize puts a standard double-hung double-pane replacement at $550–$1,100 installed, averaging $896. This Old House survey buyers paid $529 on average for double-pane.
How much will double-pane windows save on energy?
The DOE estimates ENERGY STAR windows save 7%–15% on household energy bills, roughly $71–$501 a year depending on location and the windows replaced.
What is the payback on replacing single-pane windows?
It depends on climate and price. Using sourced averages, 10 windows at $529 each against $588 a year in savings is about 9 years; at $896 each against $501 a year it is about 18 years.
Should I replace only some single-pane windows?
You can, but Modernize notes keeping even a couple of single-pane windows limits overall savings.
Sources
- Modernize, "How Much Do Double Paned Windows Cost?" (updated Aug 13, 2026); accessed Oct 29, 2026.
- This Old House, "Window Replacement Cost (2026)" (survey of 1,000 window customers) (updated Aug 11, 2026); accessed Oct 29, 2026.
- U.S. DOE, "Guide to Energy-Efficient Windows" (DOE/EE-0352) (dated Oct 2010); accessed Oct 29, 2026.
- Angi, "How Much Does Window Replacement Cost? [2026 Data]" (updated Oct 15, 2026); accessed Oct 29, 2026.
- IRS, "Energy Efficient Home Improvement Credit"; accessed Oct 29, 2026.
Figures on this page come from the third-party cost guides, manufacturer documents and government sources linked inline and listed above, checked October 29, 2026. They are not from the WindowCostEstimate cost guide or our calculator pricing model. Prices and warranty terms change; confirm with the manufacturer and compare written quotes from local installers.