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Energy Company Obligation (ECO)

The Great British Insulation Scheme and the Energy Company Obligation (ECO) offer financial support from energy suppliers to make homes more energy efficient. Here's how the schemes work.
Sarah IngramsPrincipal researcher & writer
A person in a protective mask and gloves rolls insulation in a brick attic, with wooden beams and rolled insulation nearby.

In this article

The Energy Company Obligation (ECO) is a government scheme designed to help cut carbon emissions and reduce fuel poverty.

The biggest energy suppliers have targets to help households with energy efficiency measures, and the ECO is part of those aims.

The types of measures available through ECO can include loft insulation, cavity wall insulation, solid wall insulation and boiler replacement or repair. 

The Great British Insulation Scheme is available to a wider pool of people than other iterations of the ECO scheme. It offers support to install insulation including cavity wall insulation and loft insulation.

However, in October 2025, a report by the National Audit Office (NAO) identified considerable failings in the installation of insulation funded by ECO4 and the Great British Insulation Scheme, leaving many homes in need of repair. See more on what to do if your home has been affected below. 

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What is the Energy Company Obligation?

Loft insulation

The Energy Company Obligation dictates that energy suppliers must help households reduce the costs and carbon emissions of their home heating by fitting energy-saving measures. Suppliers must focus on ways to help low income or fuel poor households, as well as those in vulnerable situations, to heat their homes. 

Energy companies can choose what energy-saving measures they want to install, how much funding they provide and the installer that does the work.

To qualify for ECO funding you must either own your home or have the permission of your landlord to do the work. Your home must also require energy efficiency upgrades - this is decided by a retrofit assessment.

Different companies provide different amounts of support and will fund different energy efficient improvements, so it's quite complicated to work out what you have access to. You're more likely to qualify if you get eligible benefits (see the full list on energy regulator Ofgem's website) and you meet the criteria set by your local authority (it can refer you for support).

But you'll still need to check with your energy provider for their exact criteria. Depending on where you live, there are different ways to check your eligibility:

The Great British Insulation Scheme

The Great British Insulation Scheme (formerly known as ECO+) offers free or cheaper insulation for your home via your energy supplier.

You can be a homeowner, landlord or tenant (renting privately or from a housing association). If you're a tenant you'll need permission from your landlord to install insulation.

To be eligible your home will need to:

  • have an Energy Performance Certificate (EPC) rating of D to G
  • be in council tax band A to D in England, or A to E in Scotland or Wales.

Funding is available for:

The government's tool to apply for support from the Great British Insulation Scheme has now closed.  However, you can still contact an energy company to find out if you can apply for the scheme.

Your energy company will arrange to assess your home if you qualify. If you need to pay anything, you'll find out after the assessment. Then you can decide whether to go ahead or not.

If you’re not eligible for help via the ECO scheme, read our tips for saving money on your energy bills or find out how to insulate your home. 

Problems with insulation fitted under government funded schemes

In October 2025, a report from the National Audit Office (NAO) revealed significant problems with the insulation fitted by the government's ECO4 scheme and Great British Insulation Scheme. 

It found that a shocking 98% of homes that have had external insulation fitted under the schemes have fundamental problems that, if left, will lead to build up of damp and mould. 

Nearly a third (29%) of the homes that received internal insulation through the schemes also need to be fixed, the NAO report found. 

The report covers work carried out between 2022 and the start of 2025, under the ECO4 and Great British Insulation Scheme, in England, Scotland and Wales. 

The NAO, which monitors how public money is spent, cited an "under-skilled workforce", businesses cutting corners and uncertainty over which standards to apply to which jobs, as some of the reasons for the issues. 

Energy Consumer Minister Martin McCluskey said the government was taking action and that the homes would be fixed "at no cost to the consumer".

What to do if you have had poor quality insulation fitted through a government scheme

Energy regulator Ofgem is managing the next steps for those affected, and has sent letters to affected properties setting out next steps for consumers. If you haven’t received a letter but think you’ve been affected, you should contact Ofgem directly. Your insulation work will then be checked by qualified professionals and you may be contacted by Ofgem or Trustmark to arrange this. If they find that the work was faulty, your installer will be asked to fix the issue at no cost to you. 

Lisa Webb, Which?'s consumer law expert, says: "Watch out for potential scammers and do not part with any money. Bear in mind that all legitimate communications about this process will use your Unique Measure Reference - you can find this information in your letter from Ogem. If you're unsure if someone contacting you is genuine, you can call Ofgem for free on 0808 169 4447 to check."

You can find out more about what to do if you are affected at GOV.UK: what to do if you have poor quality wall insulation fitted through a government scheme.

For detailed guidance on how to navigate the complaints process and what information you will need, visit Ofgem's dedicated guide to how to make an ECO4 complaint. 

Energy efficient home improvements with ECO

Energy suppliers currently offer different ECO measures. They can choose what they focus on.

Some of the most common are:

Companies can also pay for homes to be connected to district heating systems, where appropriate.

Which energy suppliers offer ECO?

The following gas and electricity suppliers must fit ECO measures. You can contact any energy supplier - it doesn't need to be the one you pay for your gas and electricity. They are: 

The amount of ECO measures each company has to fit depends on its market share.  

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