Heating and cooling account for roughly half of the average American home's energy bill — and old single-pane windows can leak 25–30% of that energy right out of your house. Use our calculator to estimate what ENERGY STAR® replacement windows could save you every year, then lock in your savings with a free quote from a top-rated local installer.
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Windows are one of the biggest weak points in a home's thermal envelope. Here's where the money goes — and how modern replacement windows stop the bleeding.
Single-pane glass conducts heat almost as fast as your furnace can produce it. The U.S. Department of Energy estimates heat gain and loss through windows accounts for 25–30% of residential heating and cooling energy use.
Clear, uncoated glass lets solar radiation pour in, forcing your AC to run longer. Low-E coatings on ENERGY STAR windows reflect infrared heat while still letting daylight through.
Worn seals, warped sashes, and failed weatherstripping let conditioned air escape year-round. New windows with quality installation dramatically cut infiltration — and eliminate cold spots near the glass.
Double- or triple-pane glass, argon gas fills, Low-E coatings, and warm-edge spacers work together to insulate 2–3× better than old single-pane units — savings that show up on every utility bill.
Answer four quick questions and we'll estimate your yearly heating and cooling savings from upgrading to ENERGY STAR certified replacement windows, based on typical U.S. energy prices and Department of Energy savings ranges.
Estimates only. Based on U.S. DOE and ENERGY STAR published savings ranges for window replacement, adjusted for climate zone, home size, and current window type. Actual savings vary by home, usage, installation quality, and local utility rates.
ENERGY STAR publishes typical annual savings for homes replacing windows with certified models. Here's how the numbers stack up in different situations.
| Scenario | Climate | Windows Replaced | Typical Annual Savings | 10-Year Savings |
|---|---|---|---|---|
| Single-pane → ENERGY STAR double-pane 1,800 sq ft ranch, gas heat + central AC |
Northern (Minneapolis) | 12 windows | $340 – $580 | $3,400 – $5,800 |
| Single-pane → ENERGY STAR double-pane 2,200 sq ft two-story, heat pump |
South-Central (Nashville) | 16 windows | $280 – $470 | $2,800 – $4,700 |
| Single-pane → ENERGY STAR Low-E 1,600 sq ft home, heavy AC use |
Southern (Phoenix) | 10 windows | $250 – $465 | $2,500 – $4,650 |
| Old double-pane → ENERGY STAR Low-E 2,600 sq ft colonial, gas heat |
North-Central (Columbus) | 18 windows | $100 – $185 | $1,000 – $1,850 |
| Single-pane + storms → ENERGY STAR 1,400 sq ft bungalow |
Northern (Buffalo) | 9 windows | $150 – $260 | $1,500 – $2,600 |
Ranges derived from ENERGY STAR national savings estimates ($101–$583/year when replacing single-pane; $27–$197/year when replacing clear-glass double-pane), scaled for home size and window count. Energy prices and results vary by market.
Efficiency incentives can shave hundreds — sometimes thousands — off your project cost. A good installer will help you claim every dollar you qualify for.
A federal income tax credit worth 30% of window costs, up to $600 per year, for ENERGY STAR Most Efficient certified windows.
Many electric and gas utilities pay $15–$100 per window for qualifying efficiency upgrades, and some states run their own programs.
Home Energy Rebate programs funded by the Inflation Reduction Act are rolling out state by state and can cover a share of efficiency retrofits — windows often qualify when bundled with insulation or HVAC work.
Your calculator estimate only becomes money in your pocket once new windows are on the wall. Here's how the free quote process works.
Answer a few quick questions about your home, how many windows you need, and your ZIP code. It takes about a minute.
We connect you with licensed, vetted window replacement pros in your area who install ENERGY STAR certified products and know your local rebate programs.
Review free, no-obligation quotes side by side. Choose the offer that fits your budget — and start cutting your energy bills from month one.
A typical homeowner replacing single-pane windows saves $300–$500 a year — plus up to $600 back at tax time. Get your free, no-obligation quote from a top-rated local installer and find out exactly what your project would cost and save.
Get My Free Quote Now →Common questions homeowners ask before replacing their windows for efficiency.