The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Most homeowners must contribute at least part of the cost.
The key variable is your household income, property energy efficiency, and whether you receive means-tested benefits. Free or fully-funded windows and doors are only available if the replacement is deemed necessary to improve the property’s Energy Performance Certificate (EPC) rating to a minimum of Band C. For the vast majority of homeowners, partial funding or no funding applies.
ECO4 and Great British Insulation Scheme eligibility
The Energy Company Obligation (ECO4) scheme runs until March 2026 and can fully fund window and door replacements for low-income households receiving benefits such as Pension Credit, Income Support, or Universal Credit (Ofgem, 2026). The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. Both schemes require that the new windows and doors meet a minimum U-value of 1.2 W/m²K for windows and 1.0 W/m²K for doors (MCS Certified, 2026).
Who cannot get free windows and doors
If your household income exceeds £31,000 per year or you do not receive qualifying benefits, you are unlikely to qualify for fully-funded replacements under government schemes (Energy Saving Trust, 2026). Private homeowners with an EPC rating of C or above are not eligible. Landlords and tenants in private rented properties may qualify only if the property has an EPC rating of E, F, or G and the landlord agrees to fund the remainder not covered by ECO4.
How to apply and what to expect
You cannot apply directly to the government. The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing. The installer will arrange a home survey to confirm the property’s EPC rating and identify necessary improvements. If fully funded, you will pay nothing. If partially funded, you cover the balance. Typical costs for double-glazed windows range from £400 to £800 per window, so partial funding still saves hundreds of pounds.
A worked example
A 1930s semi-detached house in Manchester with single-glazed windows and an uninsulated back door would typically cost £8,500 to replace all windows and the back door with A-rated double glazing. Under the Energy Company Obligation (ECO4) scheme, a household receiving Pension Credit would pay nothing because the energy supplier funds the entire installation as a qualifying energy-efficiency measure to improve the EPC from Band E to Band C. The Energy Saving Trust estimates this upgrade saves roughly £395 per year on heating bills, meaning a 0‑year payback for the eligible household. Without ECO4 eligibility, the same work would cost the homeowner £8,500, with a payback period of about 21 years based on current energy prices.Glazing is standard-rated for VAT at 20%. The zero rate for energy-saving materials covers insulation, heat pumps and solar panels; HMRC names secondary and double glazing as excluded (VAT Notice 708/6).
| Item | Figure |
|---|---|
| Upfront cost after grants | £0 (ECO4 eligible) or £8,075 (private with VAT) |
| Yearly savings | £395 |
| Payback period | 0 years (ECO4) or 20 years (private) |
| 25-year lifetime savings | £9,875 |
What homeowners often get wrong
The most common mistake is assuming the government gives cash directly to homeowners for windows and doors, rather than funding the installation through energy suppliers. Here are three frequent errors that cost people money or miss out on grants.
- Believing the scheme pays cash to you Many homeowners apply thinking they will receive a cheque or bank transfer. The reality is ECO4 and the Great British Insulation Scheme pay the installer directly, so you never handle the grant money and must use an approved TrustMark or MCS-certified contractor.
- Assuming all windows and doors qualify Some people replace every window and door in the house expecting full funding. The schemes only cover replacements needed to improve the EPC to Band C, meaning a property already at Band C or above gets no funding even if the windows are draughty.
- Ignoring the energy supplier obligation Many homeowners don’t realise their energy supplier is legally required to offer these upgrades under ECO4. If you qualify on benefits, your supplier must provide a free assessment and quote, but you must proactively contact them or use the Ofgem-approved list of obligated suppliers.
Quick reference
- ECO4 fully funds window and door replacements only for households receiving means-tested benefits like Universal Credit or Pension Credit.
- The Great British Insulation Scheme closed on 31 March 2026. It funded insulation measures only and never covered windows or glazing.
- Both schemes require the new windows to achieve a U-value of 1.2 W/m²K or lower, and doors must meet 1.0 W/m²K or lower.
- Typical payback for a privately funded window and door replacement on a 1930s semi-detached house is 20 to 25 years based on current energy prices.
- Applying for the wrong scheme can delay your project by months, check your EPC rating and benefit status first via the GOV.UK energy grants checker.
Frequently Asked Questions
No, the UK government does not offer completely free windows and doors to all. Targeted grants like ECO4 can cover full costs for low-income households receiving means-tested benefits (Ofgem, 2026).
Households receiving Pension Credit, Income Support, or Universal Credit qualify for fully-funded replacements under ECO4 (GOV.UK, 2026). The property must also need improvements to reach an EPC rating of Band C.
If your household income exceeds £31,000 per year, you are unlikely to qualify for fully-funded replacements. Lower-income households on qualifying benefits may be eligible (Energy Saving Trust, 2026).
