Energy Star Windows in California:
Rebates, Tax Credits & What to Know in 2026

Window replacement is one of the few home improvement projects that qualifies for both a federal tax credit and utility company rebates simultaneously. For Bay Area homeowners, the combination of the federal 25C Inflation Reduction Act credit, PG&E programs, and Bay Area community energy programs can reduce the effective cost of a qualifying window project by $800–$1,500 or more. Here is exactly how each program works and how to make sure you capture every dollar available to you.

What "Energy Star" Means for Windows

Energy Star is a certification program administered by the EPA. For windows, it sets minimum thresholds for two key performance metrics:

• U-factor: Measures heat transfer through the window. Lower is better. A U-factor of 0.27 means 27% of the temperature difference between inside and outside transfers through the window per hour per square foot.
• Solar Heat Gain Coefficient (SHGC): Measures how much solar radiation passes through the glass. Lower SHGC means less solar heat entering the home.

The United States is divided into climate zones for Energy Star certification. San Francisco and the Bay Area fall in Energy Star Zone 3 (Pacific / Marine Climate). The requirements for this zone are:

The Zone 3 SHGC requirement is "any" because the Bay Area benefits from solar gain in winter and needs less solar blocking than hotter inland climates. Most quality double-pane windows from reputable manufacturers meet Zone 3 requirements. Your contractor should provide you with the NFRC (National Fenestration Rating Council) label showing the certified U-factor. You will need this for tax credit documentation.

The Federal 25C Tax Credit

The Inflation Reduction Act (IRA) significantly expanded the federal energy efficiency home improvement tax credit, known as 25C. Here is what it covers for windows:

• Credit amount: 30% of the cost of qualifying exterior windows and skylights (product cost only, installation labor does not count)
• Annual cap: $600 per year for windows and skylights combined
• Who qualifies: Homeowners who own and occupy the home as a primary residence. Rental properties do not qualify.
• Product requirement: Windows must be Energy Star certified for your climate zone (Zone 3 for the Bay Area)
• How to claim: IRS Form 5695 filed with your federal tax return for the year the windows were installed

The $600 annual cap is per tax year, not per project. This means if you replace windows in two separate tax years, you can claim the credit twice, up to $1,200 total. If you are planning a large replacement project, it may be worth splitting it across December and January to maximize the credit.

Important: The 25C credit is a tax credit, not a deduction. It directly reduces your tax bill dollar for dollar. You must owe at least $600 in federal taxes to benefit from the full credit amount.

PG&E Rebates

Pacific Gas and Electric (PG&E) offers energy efficiency rebates to residential customers through its Energy Upgrade California and home energy programs. Rebate availability and amounts change periodically, so it is important to check the current PG&E rebate catalog before beginning your project.

Historically, PG&E has offered window rebates in the range of $2–$10 per square foot of qualifying window area, often as part of a whole-home energy upgrade package rather than a standalone window rebate. The key requirements are:

• Windows must meet or exceed Energy Star Zone 3 U-factor requirements
• Installation must be performed by a licensed California contractor
• Rebate applications must be submitted within 90 days of installation completion
• Some programs require a before installation home energy assessment

Check current PG&E rebates at pge.com/rebates or call 1-800-933-9555. Note that rebate programs are funded until their budget runs out, so applying early is advantageous.

Bay Area Community Energy Programs

Many Bay Area communities have their own community choice energy programs that supplement utility rebates:

• MCE (Marin Clean Energy): Serves Marin County and parts of Contra Costa and Napa. Offers energy efficiency rebates for qualifying window replacements in addition to PG&E distribution rebates.
• EBCE (East Bay Community Energy): Serves Alameda County including Oakland, Berkeley, Richmond, and Fremont. Periodically offers supplemental efficiency rebates.
• CleanPowerSF: San Francisco's community choice energy program. Efficiency programs run through SFPUC and SFEI.
• Peninsula Clean Energy: Serves San Mateo County. Offers rebate stacking with PG&E programs.

These programs change regularly. The best approach is to check your community energy provider's website or call them directly when you are ready to start your project.

How to Capture All Available Rebates: A Step-by-Step

1. Confirm your home is in a qualifying area. Your home must be your primary residence for the federal credit. For utility rebates, you must be an active PG&E customer (or your community energy provider).
2. Choose Energy Star Zone 3-certified products. Ask your contractor to confirm the U-factor of every window being installed. Get the NFRC certification information in writing.
3. Check current PG&E and community energy rebates before installation. Some programs require pre-approval or a before installation assessment. Starting this process after installation may disqualify you from certain rebates.
4. Keep all documentation. Retain the manufacturer's NFRC certificate, your contractor's itemized invoice showing the product cost separately from installation labor, and proof of payment. You need these for both the tax credit and any rebate applications.
5. File Form 5695 with your federal taxes. Your tax preparer or software will guide you through this. Line 1 of the form asks for "energy efficient home improvements." Windows and skylights go on line 1b.
6. Submit rebate applications promptly. Most programs have 90-day submission windows from installation. Do not wait.

Which Window Materials Qualify

Most modern double-pane windows from quality manufacturers meet Zone 3 requirements. That includes most vinyl, all fiberglass, and clad-wood products from major manufacturers. Basic single-pane replacements do not qualify. Low-grade vinyl with high U-factors may not qualify. Always verify the NFRC rating.

Fiberglass and clad-wood windows often achieve better U-factors than standard vinyl, sometimes qualifying for additional program tiers when programs have tiered incentives.