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Energy Star Approved Windows 2026

Energy Star approved windows are high performing windows that are certified by the National Fenestration Rating Council or NFRC (nfrc.org). Each window is independently tested and labeled by the National Fenestration Rating Council (NFRC).

In order to meet this efficiency certification (operated by the EPA), a window must meet certain standards. Specifically, these include U-value (or U-factor), which measures the overall heat transfer of a window. Additionally, the window must achieve a certain solar heat gain co-efficient (or SHGC), which measures how much solar heat enters through the window’s glass.

Of course, Energy Star approved windows will vary based on location due to variations in seasonal climate. Specifically, there are four regions in the United States, which includes the Northern, North-Central, South-Central, and Southern regions. We'll provide a list of energy star certified windows for each section as well as give you our personal favorites.

Bill - Site Editor - Publish Date - December 20, 2025
Page Last Updated August 3, 2026

Page Sections

• Energy Star Certified Explained
• Pros And Cons Of Energy Star Windows
• Main Features Of Energy Star Approved Windows
• U Value And SHGC Performance Metrics
• Which Windows Qualify For Energy Star By Region
• Energy Star Window Pricing
• Energy Star Approved Windows Q And A

Pros And Cons Of Energy Star Windows

Let’s explore the three main advantages of energy star approved windows, which include lowering your energy bills, potential tax savings, and positive affects on the environment. Then we'll turn to the downsides, which is really the initial cost of the windows themselves.

Lower Energy Bills

Energy star approved windows are obviously more energy efficient than those that are not. The less heat transfer (lower U-factor) and more efficient solar heat transfer (a function of SHGC), the lower your energy bills. And saving money on energy bills is something we can all get behind - especially as the savings mount with each passing year.

Tax Savings

Energy Star approved windows qualify for a federal tax savings in the form of a deduction for the year in which you purchased the windows. From 2021 to 2025, American consumers who purchased Energy Star approved windows, qualified for a 30% write off (on the windows themselves, but not on installation costs). I believe the cap was $600. Additionally, depending on where you live, you may also qualify for a state tax savings. Obviously, these tax savings are another great reason to opt for windows and doors that meet the Energy Star program criteria.

Better For The Environment

Reducing down your heating and cooling requirements is good for the environment. And while the amount of heating/cooling savings for one household is relatively small, when you multiply this by many millions, the environmental goodness really does begin to add up. Who doesn't feel good about that?

Disadvantages Of Energy Star Approved Windows

While there aren’t many disadvantages to buying energy efficient windows, it’s only fair to list the the main detractor - initial cost outlay. Most Energy Star approved windows are going to initially be more expensive than other non-approved windows. This isn't difficult to understand why.

Well made mainframes and sashes, between glass packages, standard upgrades that improve/reduce heat transfer all cost the manufacturer money. The good news here is that the long term return on investment is worth the initial cost. However, this is only true if you plan to stay in your home for 12 years or more (on average).

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Main Features Of Energy Star Approved Windows

Meeting the Energy Star certification is a function of high quality parts and components used during the manufacturing process.

Mainframes

These include a quality mainframe that is often characterized by multiple chambers that add strength as well as insulating properties to the window. Additionally, they will be custom molded and cut using high quality vinyl. They may contain additives such as titanium etc. for even greater strength. Finally, many of these high quality window frames will include frame inserts like Neopar that add insulating qualities. (Note that many of these features don’t apply to interior wood windows, but they would apply to the exterior cladding that many wood windows use.)

Insulated Glass Units

Most replacement and new construction windows sold today come with built in insulated glass units (or IGUs). These units are self contained and include a thin frame of their own, two panes of lowe glass, an argon gas fill and a non metallic spacer. (Triple pane windows include three panes of glass, a krypton gas fill, and two non metallic spacers.)

When we talk about creating energy star approved windows, IGUs are an incredibly important part of the process. These units use low-e glass, along with quality spacers and gas fills to greatly reduce the amount of heat or cold that can enter through the window unit.

Corner Welds

Corner welds are not materials per se, but are instead a part of the manufacturing process. Proper corner welds play a key role in creating an energy efficient window. These occur anywhere where two extrusions (the sections of the mainframe and/or sash) are welded together.

Over time, poorly made corner welds can become compromised and allow air, heat or cold to enter. This negatively affects U-value rating - one of the two key components that makes up energy star approved windows. (Compromised corner welds re most pronounced with an organic material like wood, but can affect all five of the major window materials.)

Window Spacers

A quick word on spacers. Energy efficient spacers are non metallic tabs that lay in between the panes of glass (inside the IGU) to try and minimize how the heat transfer from one pane to the other. Spacers play a small but important role in creating efficient replacement windows.

Gas Fills

Like spacers, gas fills in between the panes of glass (inside the IGU) play a small but important role in helping to make home windows ore energy efficient. The gas fills reduce the heat or cold transfer from one pane of glass to another. With double hung windows, an argon gas fills reduce the is used. However, with triple pane windows, a krypton gas fills reduce the is used.

Window Low-e Glass

Most windows sold today use a low-e glass as opposed to the clear glass of yesteryear. Low-e glass has a very thin coating on the outside of the glass pane that allows sunlight in, but not the UV rays. This makes for a much more energy efficient window. Most window companies offer multiple upgraded low-e glass packages that can have two or three layers that make for extremely efficient windows. This glass coating(s) is just one more way that companies can make energy star approved windows.

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U Value And SHGC Performance Metrics

As stated earlier, the two performance metrics used to judge and certify windows as Energy Star qualified are U-value and SHGC. Honestly, consumers don't need to know that much about these terms, but here is a simple 3 sentence definition for each.

Window U-Value Explained

The window U-value is a measure of how much heat passes through a window assembly, including the glass, frame, and spacers. It indicates the overall thermal transmittance of the window, expressed in watts per square meter per kelvin (W/m²·K). Lower U-values mean better insulation and reduced heat loss.

Pro Tip: A window's U-value measures how much heat passes through the entire window assembly. The lower the U-value, the better the window insulates your home and the lower your heating and cooling costs are likely to be.

Window SHGC Explained

The window Solar Heat Gain Coefficient (SHGC) measures the fraction of incoming solar radiation that passes through a window as heat. It indicates how much solar heat is transmitted directly and indirectly into a building through the glazing. Lower SHGC values reduce unwanted heat gain, while higher values allow more solar warmth into the space.

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Energy Star Approved Windows By Regions

There are four distinct regions within the United States, which include the following - Northern, North-Central, South-Central, and Southern. ENERGY STAR sets specific U-factor and SHGC requirements for each climate zone—stricter insulation (lower U-factor) for Northern regions, and lower SHGC for Southern climates to limit heat gain.

Here is a list of energy star approved windows for each of the four regions - many models are listed as qualified for multiple zones. Please note: this is not an exhaustive list - there are other options, but these are some of our favorites that also quality.

Northern Region ENERGY STAR Windows

Here are our picks for Energy Star approved windows for the NORTHERN REGION of the United States. In this region, the windows are optimized for optimal heating (low U-value) within these cold climates.

Note: These ENERGY STAR® recommendations are intended for the Northern Climate Zone, where minimizing heat loss (low U-value) is the primary goal. Fixed-frame windows typically achieve the lowest U-values because they have no moving sash or operating hardware.

Best ENERGY STAR® Certified Double-Hung Windows For The Northern Climate Zone

The following double-hung window series are among our top ENERGY STAR® picks for the Northern climate zone, where low U-values and strong insulating performance are especially important.

Note: ENERGY STAR® certification requirements vary by climate zone. For homes in the Northern region, prioritize windows with low U-values to reduce winter heat loss and improve overall energy efficiency.

Best ENERGY STAR® Windows For The North-Central Climate Zone

These are our recommended ENERGY STAR® window series for the North-Central region of the United States. Windows in this climate zone should provide an excellent balance of insulation, solar heat gain, and year-round energy efficiency.

Note: ENERGY STAR® certification requirements for the North-Central climate zone emphasize a balance of low U-values and appropriate solar heat gain, helping homeowners reduce heating costs during winter while maintaining efficient year-round performance.

The following are our recommended ENERGY STAR® certified double-hung windows for the North-Central climate zone. These series combine excellent thermal performance with strong air infiltration ratings, making them well-suited for homes that experience both cold winters and warm summers.

Note: The North-Central climate zone experiences both heating and cooling seasons, so homeowners should look for double-hung windows that balance a low U-value, low air leakage, and good overall energy efficiency.

Best ENERGY STAR® Windows For The South-Central Climate Zone

The following are our recommended ENERGY STAR® window series for the South-Central climate zone. These windows are designed to balance insulation with solar heat control, helping homeowners stay comfortable through both hot summers and mild winters.

Note: ENERGY STAR® requirements for the South-Central climate zone emphasize balancing low U-values with appropriate solar heat gain to improve comfort and reduce year-round heating and cooling costs.

Best ENERGY STAR® Double Hung Windows For The South-Central Climate Zone

The following are our recommended ENERGY STAR® certified double-hung window series for the South-Central climate zone. These products offer an excellent balance of energy efficiency, durability, and overall performance in warm to moderate climates.

Note: These recommendations are based on ENERGY STAR® certification for the South-Central climate zone and represent manufacturers that offer excellent thermal performance, long-term durability, and strong overall value.

Best ENERGY STAR® Windows For The Southern Climate Zone

The following are our recommended ENERGY STAR® certified window series for the Southern climate zone. These products are designed to minimize solar heat gain (low SHGC) while maintaining excellent energy efficiency in hot, cooling-dominated climates.

Note: These window series meet ENERGY STAR® requirements for the Southern climate zone and are selected for their ability to reduce solar heat gain while providing excellent overall thermal performance.

Best ENERGY STAR® Double Hung Windows For The Southern Climate Zone

The following are our recommended ENERGY STAR® certified double-hung window series for the Southern climate zone. These products are designed to minimize solar heat gain (low SHGC) while delivering excellent energy efficiency in hot, cooling-dominated climates.

Note: These double-hung window series meet ENERGY STAR® certification requirements for the Southern climate zone and were selected for their combination of energy efficiency, low solar heat gain, durability, and long-term performance.

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Energy Star Approved Windows Cost

Window price ranges are going to be huge -- wood windows can run $3500 per window installed, while vinyl windows might run $900 installed. That's a big price gap. So it's pretty tough to say what you will pay, but I am going to provide some basic price ranges that should help you know if you are paying "in the ballpark." These are installed costs (windows plus installation). Basically, I'm going to give you the top 40% price point for each window material (energy star windows are going to be in that top 40% cost for each of the five main materials).

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Energy Star Approved Windows Q And A

Below are our consumer questions and answers related to Energy Star certified windows, price quotes, brand comparisons, and so much more. If you have questions for our site editor Bill, drop him a line and he'll get back to you as soon as possible. Thanks!

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Related Topics: Double Hung Window Costs

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