ECO4 Scheme Explained: Who Qualifies

The Energy Company Obligation 4 (ECO4) is one of the most significant home energy efficiency programmes available in the UK. Administered by Ofgem and shaped by policy from the Department for Energy Security and Net Zero (DESNZ), ECO4 places a legal duty on large energy suppliers to fund insulation, heating upgrades, and other improvements for low-income, fuel-poor, and vulnerable households — at no direct cost to those households.

The scheme was originally due to close in March 2026. Following a government consultation published in January 2026, ECO4 was formally extended by nine months. It now runs until 31 December 2026, giving eligible households more time to access support before the scheme concludes.

If you are exploring grants beyond ECO4, see our guide to solar grants in the UK and our overview of the Warm Homes Plan, which is expected to succeed ECO4 from 2027.

Who Qualifies — The Benefits Pathway

The primary route into ECO4 is through receiving one of the following means-tested or disability benefits:

• Universal Credit (UC)
• Pension Credit (Guarantee Credit element)
• Income Support
• Income-based Jobseeker's Allowance (JSA)
• Income-related Employment and Support Allowance (ESA)
• Child Tax Credit (household income must be below £16,480)
• Working Tax Credit
• Housing Benefit

You must also meet the EPC band requirement (D–G) covered below. Benefit eligibility is confirmed by the installer or energy supplier via a third-party verification service; you will be asked to provide documentation such as a benefit award letter.

The EPC Band Requirement

To qualify under ECO4, your property must currently hold an EPC rating of D, E, F, or G. Homes rated A, B, or C are not eligible, as they are considered sufficiently energy-efficient already.

Homes at the lower end — F and G — are the highest priority and may receive the most extensive packages of measures. The scheme's aim is to raise every improved home by at least two EPC bands, so an F-rated property would be targeted for a D rating or better at the conclusion of the works.

ECO4 Flex — The Local Authority Route

Not everyone in fuel poverty receives a qualifying benefit. ECO4 Flex (also known as the LA Flex route) was designed to address this gap. Under Flex, local authorities, the Scottish Government, and the Welsh Government can refer households that fall outside the benefits pathway but are nonetheless in need of support.

Suppliers can meet up to 50% of their total ECO4 obligation through Flex referrals — a significant expansion from the 25% ceiling under ECO3.

Local authorities have flexibility in how they define eligible households for Flex referrals. Common criteria include:

• Household income below £31,000 per year
• A health condition exacerbated by cold or damp housing (for example, respiratory or cardiovascular conditions)
• A household member aged 65 or over
• A child aged under five living in the home

To pursue the Flex route, contact your local council directly. Some councils operate their own referral portals; others work through participating energy suppliers or approved installers. There is no single national application process for Flex — eligibility and access vary by area.

What Measures Can ECO4 Fund?

ECO4 takes a whole-house approach. Measures typically funded include:

• Insulation: loft insulation, cavity wall insulation, solid wall insulation (internal or external), underfloor insulation, and park home insulation.
• Heating: first-time central heating systems, air source heat pumps, storage heater upgrades, and smart heating controls.
• Solar panels: photovoltaic (PV) solar panels are fundable under ECO4, primarily for homes with electric heating systems or as part of a whole-house Flex package. Solar is not available to all qualifying households — the property must be assessed as suitable, and insulation measures are normally required first.
• Battery storage: in some cases, battery storage systems can be included alongside solar PV.

The exact package a household receives depends on a full retrofit assessment of the property. An approved installer will survey the home, determine the measures needed to achieve the two-band EPC uplift, and submit a proposal to the obligated supplier.

For households on low incomes who want to understand whether solar panels specifically could be funded for them, our guide to free solar panel grants for low-income households explains the full picture.

How to Apply for ECO4

There are three main application routes:

1. Via an approved installer: The most common route. Find a TrustMark-registered or MCS-certified installer who participates in ECO4. They will assess your eligibility, survey your property, and handle the paperwork with the energy supplier on your behalf. Many installers offer a free eligibility check as a first step.
2. Via your energy supplier: Contact one of the obligated suppliers (British Gas, EDF, E.ON, Scottish Power, Octopus, and others). They can direct you to their ECO4 partners or approved installer networks.
3. Via your local council (Flex route): If you do not receive a qualifying benefit but believe you meet the Flex criteria, contact your local authority to ask about referral. They will issue a declaration that the installer and supplier use to proceed.

Typical timelines run from eight to sixteen weeks between initial application and completion of works, depending on the installer's workload and the complexity of the retrofit.

What Is ECO4 — and Who Runs It?

ECO4 stands for the fourth phase of the Energy Company Obligation programme. It applies to measures installed from 1 April 2022 onwards. Three organisations share responsibility for running it:

• Department for Energy Security and Net Zero (DESNZ): sets the policy framework and legislation that defines the scheme.
• Ofgem: administers ECO4 day-to-day — it calculates supplier obligations, processes retrofit notifications, conducts audits, and investigates fraud.
• TrustMark: oversees quality assurance, ensuring that retrofit work meets technical standards and consumer protection requirements.

Under ECO4, Ofgem places a Home Heating Cost Reduction Obligation (HHCRO) on medium and large energy suppliers — including British Gas, EDF, E.ON, Scottish Power, and Octopus Energy. These suppliers must fund improvements that reduce heating costs in qualifying properties. The work is carried out by approved installers, not the supplier directly.

ECO4 vs ECO3 — What Changed?

ECO3 ran from 2018 to 2022. ECO4 introduced several important changes that raised both the ambition and the minimum standard of work funded:

• Whole-house approach: ECO4 requires a coordinated retrofit strategy rather than a single isolated measure. Insulation must generally be installed before or alongside other improvements like heat pumps or solar panels. This reflects the principle that heating upgrades are less effective in a draughty, poorly insulated home.
• Two-band EPC improvement: ECO4 requires that installed measures deliver a minimum two-band improvement to a property's Energy Performance Certificate (EPC) rating — for example, moving a home from band F to band D. This is a higher bar than ECO3 imposed.
• Expanded Flex route: Under ECO3, suppliers could meet up to 25% of their obligation via Local Authority Flex referrals. ECO4 doubled that ceiling to 50%, significantly broadening access to households not on qualifying benefits.
• Fuel poverty focus: ECO4 targets homes in the D–G EPC bands, with the lowest-rated (F and G) properties prioritised for the greatest improvements.

Is ECO4 Still Open in 2026?

Yes. Following a formal government consultation, the scheme was extended and will remain open until 31 December 2026. The government's response to the extension consultation was published on 23 January 2026 on GOV.UK. The final date for submitting Improvement Measure (IM) and Deemed Liquid Measures (DLM) applications to Ofgem is 31 March 2026 (for measures already in progress), with the overall scheme closing to new completions at year end.

There is no confirmed successor to ECO4 at the same scale. The Warm Homes Plan is the government's primary energy efficiency programme for the post-2026 period, though its detailed rules and budget allocations were still being finalised at the time of writing. Households eligible for ECO4 are encouraged to apply before the December 2026 deadline rather than wait.

How ECO4 Fits Into the Wider Grants Landscape

ECO4 is the largest active scheme for direct home energy upgrades, but it sits alongside several other programmes:

• The Great British Insulation Scheme (GBIS): a parallel insulation-focused programme that targets a broader income range (not just benefit recipients), also ending in 2026.
• The Boiler Upgrade Scheme (BUS): provides a £7,500 voucher towards the cost of an air source heat pump for owner-occupiers. ECO4 and BUS cannot be stacked for the same measure, but a household might use ECO4 for insulation and BUS for a heat pump upgrade.
• Local authority and devolved nation grants: Scotland, Wales, and Northern Ireland each run their own energy efficiency grant programmes alongside ECO4.

Understanding where ECO4 sits — and what it does not cover — helps you plan a complete retrofit strategy. Our solar grants UK guide sets out the full landscape of available funding.