What is ECO 4
What is ECO4?
ECO4 is the fourth phase of the UK government’s Energy Company Obligation – an energy-efficiency scheme for Great Britain (covering England, Scotland and Wales) running from 2022 until 2026.
The program is designed to tackle fuel poverty and reduce carbon emissions by improving the energy efficiency of homes occupied by vulnerable or low-income households. Under ECO4, the government obligates major energy suppliers to fund upgrades in eligible homes, rather than giving grants directly to homeowners. In practical terms, this means energy companies pay for insulation, heating improvements, and other measures in qualifying homes to help lower energy bills and cut carbon footprint.
One key feature of ECO4 is its “fabric-first, whole-house” retrofit approach. Unlike one-off grants for single improvements, ECO4 focuses on making a comprehensive upgrade to each home’s energy performance. It targets the least energy-efficient properties (those with EPC energy ratings of D, E, F or G), ensuring that insulation and other building fabric improvements are done before introducing new heating systems or renewables.
The goal is to maximize the overall gain – for example, a home might receive wall and loft insulation, a more efficient heating system, and possibly solar panels as part of one coordinated package. By requiring multiple measures per home, ECO4 aims for deeper energy savings than previous schemes.
Administration and quality control: ECO4 is administered by Ofgem (the energy regulator) on behalf of the government’s Department for Energy Security & Net Zero (DESNZ). Ofgem oversees the scheme’s rules and auditing, working within the TrustMark quality assurance framework to ensure that all installations meet robust standards.
All retrofit work must be carried out by TrustMark-registered installers adhering to PAS 2035/2030 retrofit standards, which guarantees a high level of workmanship and consumer protection. Unlike a traditional grant program, homeowners do not receive money directly – instead, energy suppliers decide which projects to fund and select authorized installers to carry out the work. In summary, ECO4 is a government-backed initiative where energy companies foot the bill for improving poor-performing homes, delivering whole-home energy upgrades at no or minimal cost to the residents.
Who is eligible?
ECO4 primarily targets households most in need of energy efficiency improvements, so there are specific eligibility criteria for both the people and the properties involved. Below we break down who can apply and the two main routes to qualify:
Tenure & property type
Homeowners and tenants:
Both owner-occupiers and renters can be eligible for ECO4. If you rent your home, you will need your landlord’s permission to have improvements done. The scheme covers private homes as well as social housing tenants (e.g. council or housing association properties) – as long as the property meets the energy efficiency criteria.
Low-efficiency homes only:
ECO4 is focused on properties with poor energy ratings. To qualify, a home’s current Energy Performance Certificate (EPC) rating typically must be Band D, E, F or G (the four lowest bands). Homes that are already fairly efficient (A, B or C rated) do not qualify for this scheme. Note: For privately rented homes, the bar is a bit higher – under the flexible eligibility route, **rented properties usually need to be EPC Band E, F or G (D-rated rentals may not be accepted).
Similarly, in the social housing sector, ECO4 funding is generally prioritized for homes rated E–G; D-rated social homes have very limited eligibility for measures. In short, the scheme is aimed at houses that currently waste a lot of energy, to bring them up to a decent standard.
(Tip: If you’re not sure of your home’s EPC rating, you can check if an Energy Performance Certificate exists for your address on the government EPC register or consider getting an EPC assessment. Knowing your rating will help determine if your property might qualify.)
Qualifying benefits
There are two main pathways through which a household can qualify for ECO4: “Help to Heat” (the standard means-tested route), and “ECO4 Flex” (the flexible route) for certain low-income or vulnerable households not on means-tested benefits. You only need to be eligible via one of these routes to potentially get support:
Help to Heat (HtH)
(Means-tested benefits route.)
This is the traditional eligibility route for ECO4. It’s designed for households that are already receiving specific income-related benefits. If you or someone in your household receives at least one qualifying benefit, you fall into the Help to Heat Group and meet the primary eligibility criteria. The list of qualifying benefits includes:
• Universal Credit (UC)
• Income-based Jobseeker’s Allowance (JSA)
• Income-related Employment & Support Allowance (ESA)
• Income Support
• Housing Benefit
• Working Tax Credit (WTC)
• Child Tax Credit (CTC)
• Child Benefit (subject to a household income cap)
• Pension Credit (Guarantee Credit or Savings Credit)
• Warm Home Discount Scheme rebate (Core Group eligibility)
In general, if your household is on a low-income benefit or tax credit, you are likely to qualify under Help to Heat. You will need to provide proof of receiving one of these benefits (or this may be verified through a government database when you apply).
Only one benefit is required – you do not need to be on multiple programs. Note that ECO4 tightened its criteria compared to earlier schemes, so some disability benefits no longer automatically qualify unless they coincide with the income-based benefits above.
ECO4 Flex (Flexible Eligibility)
Low-income or vulnerability route (non-means-tested).
This route allows local authorities to approve households that aren’t on the listed benefits but are still considered vulnerable to fuel poverty or the effects of a cold home. There are a few ways you can qualify under ECO4 Flex:
(a) Low income: If your total household income is below £31,000 per year (after housing costs) you may be eligible. This income threshold is used as a guideline for identifying “fuel poor” households even if they’re not on government benefits.
(b) Health or vulnerability: You can also qualify if your household includes someone with a health condition or characteristic that makes them especially vulnerable to cold temperatures. For example, many councils include criteria such as having a cardiovascular condition, respiratory illness (like COPD or asthma), limited mobility, or being immunosuppressed. These medical or vulnerability conditions would need to be evidenced (for instance, via a doctor’s note or participation in certain health programs). Importantly, the property must still have a poor energy rating (EPC band D–G) for this to apply. Under this health-based route, there isn’t an income cap – even if your income is above £31k, you could qualify due to the vulnerability, as long as the local authority deems your case meets the criteria.
(c) Other local criteria: Local councils can also declare households eligible through other “flex” criteria or referrals. For example, they might target homes in certain disadvantaged areas or use their discretion for special cases. This can vary by council under set scheme guidelines.
Local authority declaration: To access ECO4 Flex, your local authority (or in some cases the devolved government in Scotland/Wales) must verify and refer your household. This is usually done via a Local Authority Declaration or Statement of Intent, where the council confirms you meet one of the approved Flex criteria. In practice, after you apply or register interest, the council will review your situation (income proofs, medical letters, etc.) and then issue a declaration to an ECO4 provider if you’re eligible. It’s important to understand that being declared eligible by the council doesn’t guarantee installation – it means you’re now on the list that installers/energy suppliers can pick from, but the actual work still depends on an energy company agreeing to fund your home. (Energy suppliers have a limited number of projects they can do under ECO4 Flex, and will ultimately choose which homes to upgrade.) Still, getting that declaration is the key step to be considered under this route.
EPC & minimum improvement requirements
Because ECO4 is all about improving the worst-performing homes, you’ll need a qualifying EPC (Energy Performance Certificate) rating as mentioned above (Band D, E, F or G). The scheme also sets minimum improvement targets that the upgrades should achieve. In other words, if your home is accepted into ECO4, it’s not enough to just install one measure; the combination of improvements must raise your home’s energy efficiency by a certain amount. Specifically:
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If your home starts at EPC Band F or G (the lowest bands), the installed measures must boost it to at least Band D by the end of the project.
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If your home starts at EPC Band D or E, the upgrades must bring it up to at least Band C or better.
These “Minimum Requirements” ensure that the ECO4 scheme delivers a meaningful improvement – the aim is to not leave a property still below a C rating if it was reasonably achievable through the funded measures. For example, a G-rated home might receive multiple insulation upgrades and a new heating system to jump several bands to D or even higher.
A D-rated home, which is moderately inefficient, would need enough improvements to reach C, but wouldn’t be eligible for ECO4 once it’s already a C or above.
It’s worth noting that there are slight variations in eligibility for certain housing sectors: for social housing (council or housing association homes), ECO4 support is generally limited to those rated E, F, or G – D-rated social homes can only receive very specific insulation measures and are not eligible for broader upgrades. And for privately-rented homes, as mentioned, ECO4 Flex typically only covers those with E, F, or G ratings, since landlords are already required by law to have at least an E rating in most cases.
If you live in a rental that’s D-rated and you’re on benefits, you might qualify under normal Help to Heat route (since D is allowed there), but many councils focus their Flex criteria on E or below.
Checking your EPC: If you haven’t already, it’s a good idea to find out your home’s EPC rating before applying. You can usually find this on an existing EPC certificate if one was done when you bought or rented your home.
There’s also an online EPC register where you can search for your property’s report. If your home doesn’t have an EPC (for example, if you’ve lived there a long time and never needed one), you might consider getting an assessment done – it can confirm whether you’re in the D–G band needed for ECO4.
Having this information ready will speed up your eligibility check, and you’ll also need it to set a target for improvements (since the installers will calculate what upgrades are needed to hit Band C or D as required).
Scheme timeline (2022–2026)
ECO4 launched in mid-2022 and is scheduled to run until 31 March 2026. The scheme officially began its rollout in late July 2022 (with measures counted from April 2022) and will operate for a four-year period ending in March 2026.
This timeframe is set by government regulation. ECO4 is currently the final planned phase of the Energy Company Obligation program – there is no confirmation of an “ECO5” after 2026, so this is the window for households to take advantage of the scheme.
Keep in mind that while 2026 is the formal end date, the ECO4 targets could be met sooner. Each obligated energy supplier has a quota of energy savings to deliver. If they achieve their required carbon/energy savings before 2026, the scheme could effectively close early for new applicants.
In other words, funding is not unlimited; once the energy companies fulfill their obligations, they won’t continue installing measures. Homeowners are advised to apply as early as possible, rather than waiting, because demand might grow and funding caps could be reached before the official end date. It’s a bit of a “first-come, first-served” scenario – eligible projects will be taken on as long as the suppliers still have targets left to meet.
Great British Insulation Scheme (GBIS): In tandem with ECO4, the government introduced another program called the Great British Insulation Scheme in 2023. This was previously referred to informally as “ECO4+” and is meant to complement ECO4’s efforts. GBIS launched in summer 2023 and will run until March 2026 alongside ECO4. The key difference is that GBIS is a “single-measure” scheme focusing mostly on insulation.
It’s designed to provide quick, cost-effective insulation installs (like loft or cavity wall insulation) to a wider range of households. GBIS widens eligibility beyond the strict ECO4 criteria, aiming to include more middle-income families or those in slightly higher council tax bands who still could benefit from insulation improvements.
The idea is to reach as many homes as possible with simpler upgrades that cut bills – especially in response to high energy prices – without the full whole-house retrofit approach. If you find you’re not eligible for ECO4, you may want to see if GBIS could help you with a smaller measure; many energy suppliers and local councils are also involved in that scheme. (On our site, you can find more info about GBIS and how it works.)
How it works
If you qualify for ECO4, the process from application to installation generally goes as follows:
1. Check eligibility and apply: You’ll start by filling out an eligibility form or using an online checker (for example, through your local council or an ECO installer’s website). This will ask for details about your household income or benefits, the people living in your home, and the property’s current EPC rating.
The information is used to confirm whether you meet the ECO4 criteria – in some cases, this may be automatically verified (for instance, your benefit status might be checked via a government database, or a council officer will review your documents if you’re applying through ECO4 Flex). If you appear to qualify, you’ll move on to the next step.
(Tip: On our site, you can use the Eligibility Checker tool to quickly see if you might be eligible and get the process started.)
2. Home survey by a TrustMark installer: If you’re deemed eligible, the next step is a free home survey. An approved retrofit assessor or surveyor from a TrustMark-registered installation company will contact you to schedule a survey of your property. During this visit, they will inspect your home’s current insulation levels, heating system, windows, etc., and may ask about any issues (drafts, damp, high bills) to identify what measures your home needs.
This assessment is done in line with the PAS 2035 retrofit standards – essentially a thorough energy audit of the house. The assessor will also confirm your home’s EPC rating (or conduct an updated EPC assessment) as a baseline. Don’t worry, this survey is at no cost to you and is a normal part of the process.
3. Recommended measures & approval: Based on the survey, the installer will develop a proposed retrofit plan for your home. This will typically include a package of measures (for example, they might propose installing loft insulation, cavity wall insulation, and a heating system upgrade if those will bring your home to the required standard).
The plan is designed to meet ECO4’s rules – for instance, ensuring that if you’re an F band now, the measures should lift you to at least D. The proposal is then submitted to the energy supplier or managing agent overseeing the funding for approval. They will check that the plan makes technical and economic sense and that it will achieve the necessary improvement score under the ECO4 scheme.
You might be asked to review or sign off on the proposed works as well. Once approved, you’ll be given the go-ahead for installation.
(If for some reason a measure isn’t approved – say, a heat pump in a home that isn’t suitable – the installer might adjust the plan with an alternative measure.)
4. Installation of upgrades: Now the real work begins! The installer’s team will schedule the work and install the agreed energy efficiency measures in your home. All installations under ECO4 are free of charge (no upfront cost) to the resident – the cost is covered by the energy company obligation.
The exact timeline for installation can range from a single day for something like loft insulation, to multiple days or weeks for more extensive work (for example, solid wall insulation or a full heating system replacement). The good news is that all installers must follow strict quality standards. ECO4 projects are carried out by certified professionals under the PAS 2035 framework, and every installer must be TrustMark accredited to participate.
This means the work is done to a high standard and comes with appropriate guarantees. Throughout the installation, there may be inspections or oversight by a Retrofit Coordinator – a qualified specialist who ensures that the measures are being installed correctly and safely as part of the whole-house plan.
You won’t have to pay anything during this process; if a contribution is ever required for something (which is uncommon and only if you agree to, say, a higher spec item), that would be made clear upfront. In the vast majority of cases, ECO4 improvements are fully funded.
5. Post-installation checks and results: After the installation is complete, the installer will perform a post-retrofit assessment to verify the new energy performance of your home. Essentially, they update your home’s EPC rating or SAP score to see if the target band (C or D, depending on where you started) has been met.
As long as the Minimum Requirement is achieved and everything is installed as per standards, the project is considered successful. You should receive documentation for the work – for example, an updated EPC certificate and any warranties for the installed measures. Ofgem may audit projects as well, which is a behind-the-scenes process you typically wouldn’t need to worry about (it’s to ensure the energy companies and installers followed all rules).
Finally, you get to enjoy a warmer, more efficient home! Your energy supplier or installer may provide advice on using any new systems (like a thermostat or heat pump controls) effectively.
Any work done comes with guarantees (through TrustMark and other schemes) for your peace of mind. In the end, not only should your home have an improved EPC rating, but you should also notice lower energy bills and increased comfort.
(If you have any issues after installation, there are protections in place – you can contact the installer (or us, if we coordinated your project) for support. All ECO4 work is backed by quality assurance, so problems are rare and are fixed at no cost to you.)
Supported eco measures
ECO4 can fund a wide range of home energy improvements, essentially anything that significantly improves efficiency or heating in a homeofgem.gov.uk. Below are some of the main measures that are typically offered through the scheme. (Each item is linked to a page with more details on how it works and its benefits – so feel free to click to learn more about any measure that interests you.)
Loft insulation:
Insulating your loft or attic space to prevent heat escaping through the roof. This is one of the most cost-effective upgrades – it keeps your home warmer in winter and cooler in summer by creating a thermal barrier under your roof. Homes with little or no existing loft insulation (common in older properties) can see a big improvement in energy efficiency after this measure.
Cavity wall insulation:
Many houses built after the 1920s have exterior walls made of two layers with a gap (cavity) between them. Cavity wall insulation fills that gap (usually with beads or foam), reducing heat loss through your walls. It’s a quick install and can save a substantial amount on heating bills. If your home has uninsulated cavity walls, ECO4 might cover this as a priority measure because it’s low-cost and effective.
Solid wall insulation (internal or external):
Homes with solid walls (brick or stone walls with no cavity, often pre-1930s buildings) lose a lot of heat. Solid wall insulation involves adding insulating material either internally (inside your rooms on the external walls) or externally (added to the outside facade and then rendered).
This is a more extensive retrofit but can dramatically improve a cold, hard-to-heat home. ECO4 may install internal or external wall insulation for qualifying homes – external insulation is common for houses, while internal insulation might be used for flats or where preserving outside appearance is important.
Underfloor insulation:
If you have a suspended timber floor (common in older or timber-framed houses where there’s an air gap beneath the floorboards), insulating under the floor can stop drafts and heat loss through the floor. This usually involves accessing the crawl space or cellar and fitting insulation between the joists. It can make a noticeable difference in comfort, especially in winter, by keeping your floors warmer.
First-time central heating:
ECO4 can install a brand new central heating system in homes that don’t currently have one. For example, if you rely on electric room heaters or old storage heaters because there’s never been a gas boiler and radiator system in your home, the scheme might fund a full central heating installation (boiler plus radiators and controls) for the first time.
This is a significant upgrade that can greatly improve heating efficiency and reduce costs, especially if gas central heating or a modern equivalent is much cheaper than your current setup. (Note: if your home is off the gas grid, ECO4 might look at alternatives like an oil boiler replacement or a heat pump – the goal is to ensure you have an efficient primary heating source.)
Boiler upgrades & heating controls:
Replacing an old, inefficient boiler with a new A-rated condensing boiler can save energy and money. Under ECO4, if your boiler is really outdated or broken and you qualify, they might install a new gas boiler (or even convert to a heat pump, depending on the circumstances). Along with the boiler, installers often add smart heating controls – things like a programmable thermostat, TRVs (thermostatic radiator valves), and smarter timers – to help you heat your home more effectively.
These controls allow you to schedule heating and avoid wasting energy when you don’t need heating on. Even if you already have a decent boiler, adding better controls can be a measure in some cases to improve efficiency.
Air-source heat pumps:
An air-source heat pump is a low-carbon heating system that uses electricity to extract heat from the outside air and pump it into your home (like a reverse refrigerator). Heat pumps are an eligible measure under ECO4, especially as a replacement for old electric heating or as part of a multi-measure upgrade for off-gas-grid homes. They can greatly lower carbon emissions and work best in well-insulated homes. Under ECO4’s fabric-first approach, a heat pump might be installed after insulation measures, to ensure the home is suitable.
If you qualify, the scheme could fully fund the supply and installation of an air-source heat pump, which otherwise is quite an expensive technology to install.
Solar photovoltaic (PV) panels:
While insulation and heating improvements come first, ECO4 also allows for solar PV panels to be installed as part of a whole-house plan. Solar panels on your roof generate free electricity from sunlight, which can help lower your electric bills. In ECO4, solar PV is often considered once the “priority” measures (insulation, heating) are done – it’s like the cherry on top to maximize your home’s efficiency and reduce bills further.
Not every home will get solar panels through ECO4, but it’s possible if your home is a good candidate (enough sun exposure, suitable roof, and already insulated/heated to standard). Solar can especially benefit households that use a lot of daytime electricity or have electric-based heating.
Each home will get a different mix of measures based on what it needs to reach the required EPC band cost-effectively. The examples above are some of the most common ECO4 improvements.
All upgrades are installed by qualified professionals and come with the appropriate certifications. If you qualify for ECO4, you won’t have to pick and choose – the experts will recommend what your home truly needs, and it will all be arranged free of charge under the scheme.
The end result is a more energy-efficient home: warmer, cheaper to heat, and often with modern systems that add value to your property.