ECO4 scheme double glazing — can you get free windows?
The UK government-funded scheme that pays for new windows for qualifying low-income and fuel-poor households. Here’s exactly how it works in 2026.
Energy Company Obligation (ECO4) is the UK government scheme that funds energy-efficiency upgrades for low-income and fuel-poor households. For qualifying homeowners, it can pay for double glazing, insulation, and heating upgrades — sometimes in full, sometimes with a contribution required. This guide explains who qualifies, what’s covered, and exactly how to apply.
Quick eligibility check
You may qualify for ECO4 double-glazing funding if your household meets any one of these criteria:
- You receive any of these benefits: Universal Credit, Pension Credit, Income-based JSA, Income-related ESA, Child Benefit (within income caps), Child Tax Credit, Working Tax Credit, Housing Benefit, Income Support
- Your home has an Energy Performance Certificate rating of D, E, F or G
- You’re in fuel poverty (spending more than 10% of income on energy)
- A member of your household has a health condition that makes them vulnerable to cold
Full eligibility criteria at gov.uk/energy-company-obligation.
What ECO4 covers
- Single glazing → double glazing — usually fully funded for qualifying households
- Cavity wall insulation — usually fully funded
- Loft insulation — usually fully funded
- Heating upgrades — new efficient boiler or heat pump; usually part-funded with a customer contribution
Not covered: upgrading existing double glazing to triple; replacing post-2015 double glazing; cosmetic replacements; second homes.
How to apply — step by step
- Check your EPC rating — free lookup at gov.uk/find-energy-certificate. Your home needs a D rating or worse to qualify for most ECO4 measures
- Contact an ECO4-approved installer directly, or apply via your energy supplier (British Gas, Octopus, E.ON all run ECO4 programmes). Installers are obliged to submit applications on your behalf
- Provide evidence of qualifying status — a recent benefit statement, Tax Credits letter, or GP letter for vulnerability criteria
- Home assessment — an ECO4-registered surveyor visits to confirm the work is eligible and calculate the funding
- Installation — if approved, work is carried out and the installer claims the subsidy directly from the scheme
Common reasons applications fail
- EPC rating is C or higher — home is already “energy efficient enough” per the scheme
- Existing double glazing less than 15 years old — replacement for cosmetic reasons isn’t funded
- Incomplete benefit documentation — keep recent award letters handy
- Property is tenanted and the landlord hasn’t applied — tenants can’t apply directly for most measures
- Second home or holiday home — only primary residences qualify
Scotland — Home Energy Scotland loans
If you live in Scotland, ECO4 applies but so does the separate Home Energy Scotland loan scheme. Interest-free loans up to £15,000 for energy-efficiency upgrades, available to any Scottish homeowner regardless of income (subject to credit check). Excellent option if you don’t qualify for ECO4’s means-tested funding but want to finance work at 0% interest.
Wales — Nest scheme
Welsh households on qualifying benefits can apply for free energy-efficiency upgrades via the Nest scheme (run by Welsh Government). Covers insulation, boilers, and some glazing.
What if you don’t qualify for ECO4
Not everyone qualifies, but you can still save significantly by getting 4 competitive quotes rather than accepting one national-chain quote. The typical £2,000-£4,000 spread between cheapest and most expensive quote for identical spec means comparison alone delivers a similar saving to some ECO4 contributions.
Frequently asked questions
Do I have to apply through Findfitter?
No. ECO4 is a government scheme — you apply through any ECO4-approved installer directly, or via your energy supplier. Findfitter’s quote-matching service is separate and doesn’t route ECO4 applications. If you qualify for ECO4, apply via the gov.uk route first; if you don’t qualify, use Findfitter to get competitive quotes paying yourself.
How long does ECO4 approval take?
Typically 4-8 weeks from initial application to installation. The home assessment is usually within 2-3 weeks; approval another 2-3 weeks; installation scheduled 2-4 weeks after approval. Busy periods (October-January) can extend the timeline.
Can I combine ECO4 with Home Energy Scotland loans?
Not for the same measure. But you can use ECO4 for one (say, insulation) and a HES loan for another (say, windows) — as long as each application is separate. Home Energy Scotland can advise on combinations.
When does ECO4 end?
ECO4 runs to March 2026, with a replacement scheme (ECO5) under government consultation. If you qualify now, apply now — transitions to a replacement typically introduce 2-4 month delays.
What if I own the home but rent it out?
Landlords of properties with EPC rating D-G are eligible for ECO4 on the property itself, not for their own home. They must commit to maintaining the property as a rental for a minimum period. Applications go via the standard ECO4 installer route — tenants can encourage landlords to apply but cannot apply themselves.
Sources
From homeowners like you
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