Is ECO4 really free? Contributions, repayment and what to ask

Sources: Ofgem, homeowners and tenants. Checked 19 October 2026.

How ECO4 is paid for

ECO4 is an obligation on energy suppliers to fund energy-saving work in homes, overseen by Ofgem. The money does not come from a government grant paid to you. A supplier, or an installer working for one, funds measures that count towards the supplier's obligation. That is why the supplier decides what to fund: it is weighing the cost of the work against what the work counts for under the scheme rules.

When you might be asked to contribute

Ofgem says suppliers decide which measures to fund and how much, so you may be asked to contribute. It does not comment on how large contributions are, and it advises shopping around. Contributions are more likely when:

• the measure costs more than the supplier is willing to fund for your home;
• you ask for something extra beyond what the retrofit assessment recommends;
• the work involves a larger job, such as solid wall insulation, where costs vary widely.

The protection is simple: Ofgem says to agree to ECO measures only once you have received a contract. The contract should show exactly what is being installed and whether you pay anything.

Free, contribution or not eligible: how it usually breaks down

Do you have to pay back an ECO4 grant?

ECO4 is not a loan. Ofgem's consumer guidance describes funded measures and possible contributions, not repayment. The real question is not "will I have to pay it back" but "will I be asked to pay anything up front", and the contract answers it.

How much is ECO4 worth?

There is no fixed ECO4 grant value. Sites that promise "up to £15,000" or a set amount are not quoting an official figure. What your home gets depends on a retrofit assessment and on what a supplier decides to fund. ECO4 also cannot be blended with other government grants for the same measures, so funding from two schemes for one job is not allowed.

Five questions to ask before you sign

1. Which obligated energy supplier is funding this?
2. Exactly which measures are included, and which are not?
3. Will I be asked to contribute anything, and how much?
4. Is the installer on the TrustMark register?
5. What guarantee comes with the work, and who provides it?

If a caller cannot answer these, GOV.UK's advice is to check with your council or the energy supplier they claim to represent.

Words to be careful with

After the work: guarantees and problems

GOV.UK says that if you are unhappy with work or products installed under the scheme, you should contact the installer or the company that guaranteed the work, and if they do not solve the problem, contact Citizens Advice. For solid wall insulation there is a separate GOV.UK route, because GOV.UK notes quality issues with some solid wall insulation fitted through the scheme. Keep every document you are given, including the guarantee, so you can use these routes if you need them.

If you rent

For private tenants, GOV.UK says the home must be rated E, F or G and you need the owner's permission for the work. If a contribution is requested, it is a question for you and your landlord to settle before anything is signed: the contract should say who pays what.

Next steps

Use the checker on this page to see if you might qualify, or check if you qualify for ECO4 with the full rules. Our guide on how to apply for ECO4 explains each route. ECO4 runs until 31 December 2026.

Questions