ECO4 (Energy Company Obligation, phase four) runs to March 2026 and obliges larger energy suppliers to pay for energy efficiency and heating upgrades in the least efficient homes occupied by lower-income households. For households that qualify, the work is often fully funded. This guide helps you work out whether you're likely to qualify before you speak to an installer.
Quick self-assessment: the three tests
Almost every ECO4 approval comes down to three things:
- Household income or benefits — someone in the home receives a qualifying means-tested benefit, or your council refers you under LA Flex.
- Property efficiency — your EPC rating is low (usually D–G if you own the home, E–G if you privately rent).
- Tenure — owner-occupiers and private tenants (with landlord permission) can qualify. Social housing has separate rules and is limited to E–G properties.
If all three look like a yes, it's worth getting assessed.
Qualifying benefits
You are likely eligible on the income route if a member of the household receives any of:
- Universal Credit
- Pension Credit (Guarantee or Savings Credit)
- Income-based Jobseeker's Allowance (JSA)
- Income-related Employment and Support Allowance (ESA)
- Income Support
- Child Tax Credit or Working Tax Credit
- Housing Benefit
- Child Benefit (subject to household income thresholds)
No benefits? LA Flex may still apply
ECO4 Flex (LA Flex) lets local authorities refer households that don't receive benefits but are on a low income, are vulnerable to cold, or live in fuel poverty. Each council sets its own income threshold and criteria, so it's worth checking your council's ECO4 Flex page even if you're not on benefits.
The EPC rule — and why it matters most
ECO4 is a whole-house scheme: it targets the worst-performing homes and expects a meaningful EPC improvement after the work. Homes already at band C are generally out of scope. Homes in bands E, F and G are prioritised, and insulation usually has to be brought up to standard before or alongside a heating measure — you can't normally get a heat pump under ECO4 in an uninsulated home.
What ECO4 can pay for
- Loft, cavity wall, solid wall, underfloor and room-in-roof insulation
- First-time central heating
- Air source heat pumps (usually replacing electric, oil, LPG or coal heating)
- Broken or inefficient heating system repairs and replacements
- Heating controls such as smart thermostats and TRVs
- Solar PV — in some cases, alongside a primary heating or insulation measure
Note that ECO4 rarely funds a straight gas boiler swap, and a measure cannot be funded twice — you cannot combine ECO4 with the Boiler Upgrade Scheme for the same heat pump.
Will I have to contribute anything?
Many ECO4 jobs cost the household nothing. Where the grant doesn't fully cover the measure, the installer may ask for a contribution. Get any contribution in writing before signing, and never pay a deposit to a company that cold-called you.
How to apply
There's no government application portal. You apply through an obligated energy supplier or an installer delivering work on their behalf — you don't need to be that supplier's customer. The process is normally: eligibility check → home survey and EPC assessment → confirmation of funded measures → installation → post-install EPC lodged.
If you don't qualify
Plenty of households sit just outside ECO4. Other routes are still open: heat pump grants such as the £7,500 Boiler Upgrade Scheme, solar panel grants and 0% VAT, and Home Energy Scotland loans if you're in Scotland.
Next step: talk to installers who handle grant-funded work
Eligibility is confirmed by an assessor, not by a website. Tell us about your home and we'll match you with vetted UK installers — including those who work with grant-funded schemes — so you can get a straight answer and compare solar or heat pump quotes side by side.