ECO4 Insulation Grant: What It Is and Who Qualifies

What ECO4 actually is

ECO4 is the fourth phase of the Energy Company Obligation, a legal duty placed on larger energy suppliers to pay for energy-efficiency and heating improvements in lower-income homes. It is not a grant you claim from the government, and you do not apply to Ofgem. Instead, obligated suppliers meet their target (formally the Home Heating Cost Reduction Obligation) by funding work delivered through accredited installers. In practice, that means the money reaches you as a fully or partly funded insulation or heating job, arranged through a supplier, an installer, or your local council.

The single most important fact, and the one most other websites get wrong, is that ECO4 is open. The scheme was extended by nine months, from its original end date of 31 March 2026 to 31 December 2026, in the government response published on 23 January 2026. So if you have read that ECO4 has closed, that information is out of date. What genuinely has closed is the separate Great British Insulation Scheme (GBIS), which ended on 31 March 2026. If you are unsure which is which, our ECO4 vs GBIS comparison lays out the differences plainly.

Where ECO4 applies (and where it does not)

ECO4 runs across Great Britain only: England, Scotland and Wales. It does not operate in Northern Ireland, where the equivalent support is the Affordable Warmth Scheme and NISEP instead. If you live in Northern Ireland, see our Northern Ireland insulation grants page rather than relying on any ECO4 information.

Within Great Britain, ECO4 sits alongside nation-specific schemes. In England it runs beside the council-delivered Warm Homes: Local Grant. In Scotland it works with the Home Energy Scotland Grant and Warmer Homes Scotland. In Wales it runs alongside Warm Homes Nest. A good installer will help you find the best combination for your home and nation.

Is there an ECO5 coming after this?

No. There is no ECO5 and no successor supplier obligation. This was confirmed at the November 2025 Budget. That matters for planning: ECO4 is currently the last phase of the Energy Company Obligation, so the extension to 31 December 2026 is not a stepping stone to another round of the same scheme. Beware of any website or cold caller claiming there are "new free ECO5 grants from April 2026" or similar. Those schemes do not exist, and that language is a common feature of the insulation grant scams we warn about.

Government funding for home upgrades continues through other routes, chiefly the Warm Homes Plan umbrella and the local grants it funds, but those are separate schemes with their own eligibility, not a renamed ECO.

Who qualifies for ECO4

ECO4 is aimed at lower-income and vulnerable households. There are two main ways in: the benefits route and the ECO4 Flex (council) route.

The benefits route

You may qualify if someone in the household receives one of the qualifying means-tested benefits:

• Universal Credit
• Pension Guarantee Credit
• Pension Savings Credit
• Income Support
• Income-based Jobseeker's Allowance (JSA)
• Income-related Employment and Support Allowance (ESA)
• Child Benefit (within income thresholds)
• Housing Benefit
• Working Tax Credit
• Child Tax Credit

The ECO4 Flex (LA Flex) route

You do not have to be on benefits to get help. Under ECO4 Flex, also called LA Flex, your local council can refer low-income households that are not on the qualifying benefits, following the criteria in its published Statement of Intent. Councils can use this route for up to 50% of a supplier's target. Criteria vary by council but usually consider household income, health conditions made worse by a cold home, and area-based fuel-poverty indicators. If you are not on benefits, this is often the way in, and we cover it further on our insulation grants if you are not on benefits page.

Your property's EPC and tenure

ECO4 is targeted at the least efficient homes, so your Energy Performance Certificate (EPC) rating is central. The rules differ by tenure:

Because nearly every insulation grant is gated on a poor EPC, the first thing to do is check your certificate. You can look it up free on the government EPC register. If you are a renter, see our dedicated guide to insulation grants for private tenants, which explains the owner-permission step.

You can confirm your own eligibility in a few minutes using our independent eligibility checker.

How ECO4 works: whole-house, fabric first

ECO4 is deliberately a "whole-house" scheme, not a menu of single quick fixes. It follows a fabric-first principle: insulate and reduce heat loss before, or alongside, upgrading the heating. A compliant ECO4 project starts with a retrofit assessment and is overseen by a Retrofit Coordinator under the PAS 2035 standard. If an installer wants to sell you one measure without any assessment, that is a warning sign, and you should read our notes on quality and standards below.

In practice this means the assessor looks at the whole property and recommends a package that will move the home up the efficiency scale, rather than, say, filling the loft and stopping there while the walls stay cold.

What insulation ECO4 funds

ECO4 can fund a broad range of insulation and heating measures. The insulation measures most relevant to homeowners and tenants, with typical unsubsidised costs from the Energy Saving Trust for context, are set out below. Grants matter most where the unsubsidised cost is highest.

Non-standard homes such as park homes can also be covered, though the assessment is different. For the full picture of what upgrades typically cost with and without funding, see our cost of insulation guide.

Is ECO4 really free?

Often, but not always. For the cheaper, most common measures such as loft or cavity wall insulation, an eligible household is frequently fully funded. For the highest-cost measures, especially solid wall insulation, a supplier may request a contribution rather than covering 100% of the cost. So the honest framing is: often fully funded, but a contribution can be asked for on expensive work. We explain this in more depth on our are insulation grants really free page. Applying to the scheme itself is always free, and you should never pay upfront or start work before you have written approval.

How to apply for ECO4

You do not apply to Ofgem, and there is no central ECO4 application form. There are three practical routes:

• Through an obligated energy supplier. Contact a large supplier's ECO team or use their referral process. Note that suppliers may stop taking new referrals before 31 December 2026 once they have met their target, so acting earlier in the year is sensible.
• Through an accredited installer who works with obligated suppliers and can arrange the retrofit assessment.
• Through your local council if you are applying via the ECO4 Flex route, which is the council-referred pathway for lower-income households not on benefits.

This page is an explainer. For a full walkthrough of the steps and documents, see our how to apply guide. If you specifically want the transactional application detail for ECO4, our sibling site eco4application.co.uk covers the application process in depth. You can also read the official rules on the Ofgem Energy Company Obligation pages and the government's ECO4 end-date extension response.

Quality, standards and avoiding scams

Grant-funded work must be done to recognised standards. Insist that the installer is registered with TrustMark and works to PAS 2035 (retrofit) and PAS 2030 (installation). A compliant ECO4 job always begins with a retrofit assessment and a Retrofit Coordinator, never a doorstep sale of a single measure.

Two specific warnings. First, the National Audit Office found in October 2025 that around 98% of external-wall-insulation jobs under ECO4 and GBIS had defects, prompting free TrustMark "Find and Fix" audits; if you have had grant-funded external wall insulation recently, it is worth checking whether your install needs auditing. Second, spray-foam loft insulation is a known mis-selling trap that can block mortgages, so be wary of cold callers pushing it. Real schemes are accessed through official channels, not unsolicited calls, texts or doorstep sellers. Our insulation grant scams guide covers the red flags in full.

A note on 0% VAT

Even if you do not qualify for ECO4, there is a saving worth knowing about. In Great Britain, installing qualifying insulation has been at 0% VAT under the Energy-Saving Materials relief, which helps able-to-pay households self-fund. Rates and end dates can change and treatment in Northern Ireland can differ, so confirm the current position against HMRC VAT Notice 708/6. This is general information, not tax advice.

Next steps

If you think ECO4 might apply to you, check your EPC, use our eligibility checker, then compare your options across our grants and funding hub. When you are ready to be matched with an accredited route, you can send us your details through our contact form and we will point you to the right official channel. We install nothing and run no grant; our job is simply to help you reach the genuine scheme, for free.