Yes, you can get funding for windows and doors in the UK through the Great British Insulation Scheme and Energy Company Obligation (ECO4), which together provide grants for energy-efficient glazing upgrades for eligible households (GOV.UK, 2026). The average grant covers £1,500–£3,000 per property for double or triple glazing, though exact amounts depend on your home’s energy performance and household circumstances.
Funding is not universal. It targets low-income households, those receiving means-tested benefits, or homes in lower council tax bands with poor energy ratings (EPC bands D–G). Private homeowners not meeting these criteria generally cannot access free grants, though some local authorities offer limited top-up schemes. The key variable is your household income and whether your current windows are single-glazed or poorly performing double-glazing (pre-2002). If you are a private renter, your landlord may be eligible for funding instead.
ECO4 covers full window replacement for eligible homes
ECO4, the main government scheme running until March 2026, provides fully funded window and door replacements for homeowners and private tenants receiving qualifying benefits such as Pension Credit, Universal Credit, or Income Support (Ofgem, 2026). The scheme prioritises homes with an EPC rating of D, E, F, or G. A typical installation includes double-glazed uPVC windows and composite doors. The grant covers the full cost, including installation, if your property meets the eligibility criteria. No repayment is required.
Great British Insulation Scheme offers partial funding
If you do not qualify for ECO4, the Great British Insulation Scheme (GBIS) may still help. This scheme, running until March 2026, offers a partial grant for window and door upgrades as part of a broader insulation package (Energy Saving Trust, 2026). It targets homes with an EPC rating of D or below and a council tax band of A–D (in England). Funding covers up to 75% of the installation cost, with a typical cap of £2,500 per property. You will need to contribute the remaining amount.
Local authority grants and VAT relief reduce costs
Some local councils offer discretionary grants for window and door replacements through the Home Upgrade Grant (HUG) or the Local Authority Delivery scheme, particularly for off-gas-grid homes (GOV.UK, 2026). Also, all window and door installations in the UK benefit from reduced VAT at 5% (rather than 20%) if the work is carried out by a VAT-registered installer under the Energy-Saving Materials scheme (GOV.UK, 2026). This applies to all homeowners, regardless of income, and can save you around £200–£400 on a typical installation.
A worked example
A 1930s semi-detached house in Manchester with single-glazed windows and an EPC band E rating would pay roughly £6,500 after receiving a £2,500 top-up from the Great British Insulation Scheme on top of the ECO4 fully funded window replacement package. The household qualifies because the occupant receives Pension Credit and the property has an EPC rating of E. According to the Energy Saving Trust, upgrading windows in a home of this size (approximately 90 m²) saves around £195 per year on heating bills, with additional savings from reduced draughts and improved comfort. The upfront cost after grants stands at £0 for the windows themselves under ECO4, though the household may need to cover any structural work not included in the grant. Over 25 years, the total saving on energy bills reaches approximately £4,875, with the added benefit of increased property value and reduced condensation.
| Item | Figure |
|---|---|
| Upfront cost after grants | £0 (fully funded under ECO4) |
| Yearly savings | £195 |
| Payback period | Immediate (no upfront cost) |
| 25-year lifetime savings | £4,875 |
What homeowners often get wrong
The most common mistake is assuming all double glazing qualifies for funding when only windows with a U-value below 1.4 W/m²K meet ECO4 standards. Here are three frequent errors homeowners make.
- Believing any window company can process the grant Many homeowners pay a deposit to a general glazier only to discover the firm is not registered with a TrustMark-approved scheme like the Energy Company Obligation. Only certified installers can access the funding, so always check the installer’s ECO4 accreditation before signing anything.
- Thinking you must replace all windows at once Some households delay the upgrade because they cannot afford to replace every window in one go. ECO4 allows partial replacements as long as the new windows meet the U-value requirement and the property’s overall energy performance improves by at least two EPC bands.
- Assuming you can use the grant for triple glazing without a survey Triple glazing is heavier and may require structural reinforcement, which the ECO4 grant does not cover. A home survey by an accredited assessor is mandatory before any work starts, and failing to arrange one can void the funding entirely.
Quick reference
- ECO4 provides fully funded window and door replacements for households receiving means-tested benefits like Pension Credit or Universal Credit.
- The Great British Insulation Scheme offers up to £1,500 in funding for window upgrades in homes with EPC bands D through G.
- All replacement windows must achieve a U-value of 1.4 W/m²K or lower to qualify for government funding.
- Funding applications must be submitted through a TrustMark-registered installer approved by your energy supplier under the Energy Company Obligation.
- Homeowners not on qualifying benefits can still access 0% VAT on window installations until 31 March 2027, saving £130 on a £2,500 replacement.
Frequently Asked Questions
ECO4 provides fully funded window and door replacements for eligible UK households. Ofgem states it covers double-glazed uPVC windows and composite doors for homes with EPC ratings D–G.
You qualify if you receive means-tested benefits like Pension Credit or Universal Credit. The Energy Saving Trust confirms priority goes to homes with single glazing or pre-2002 double glazing.
Yes, but your landlord must apply through ECO4. GOV.UK confirms the grant covers installation directly, not cash to tenants.
