ECO4 Scheme Explained: How to Get Free Insulation and Heating in the UK
The ECO4 scheme funds free insulation and heating upgrades for eligible UK households, covering measures worth up to £10,000 or more per property. Around 3 million homes are expected to benefit before the scheme closes in December 2026. If you receive qualifying benefits and live in an energy-inefficient home, you could get loft insulation, wall insulation, a new boiler, or even first-time central heating at no cost. This guide explains who qualifies, what is covered, how to apply, and what to watch out for.
What is ECO4?
ECO4 stands for Energy Company Obligation 4. It is a UK government scheme that legally requires large energy suppliers (British Gas, EDF, E.ON, OVO, Scottish Power, and Octopus) to fund energy efficiency improvements in low-income and fuel-poor households. The suppliers pay for the work through levies on all customer bills, so eligible households receive the improvements at no direct cost.
The scheme launched in April 2022 and runs until December 2026. It replaced ECO3, which ended in March 2022. ECO4 focuses on a "fabric first" approach, meaning insulation is prioritised before heating system replacements, because reducing heat loss delivers the biggest long-term savings.
ECO4 aims to upgrade homes to at least EPC Band D where practical. If your home is currently rated E, F, or G, the scheme will fund whatever combination of measures is needed to bring it up. Use our EPC improvement planner to see what upgrades your property needs.
Who qualifies for ECO4?
There are two routes to eligibility: the benefits route and the ECO4 Flex route.
Benefits route
You qualify if you receive any of the following means-tested benefits and your property has an EPC rating of D, E, F, or G:
Universal Credit, Pension Credit (Guarantee Credit), Child Tax Credit (income under £16,385), Working Tax Credit (income under £16,385), Income Support, income-based Jobseeker's Allowance (JSA), income-related Employment and Support Allowance (ESA), or Housing Benefit.
You must be the homeowner, or a private tenant with your landlord's permission. Social housing tenants can also qualify, with the housing association acting as the applicant.
ECO4 Flex route
If you do not receive qualifying benefits but are on a low income and live in an energy-inefficient home, your local council can refer you through ECO4 Flex. Councils set their own eligibility criteria, but common qualifications include household income below a local threshold, living in a property rated E, F, or G, or being identified as vulnerable to the effects of cold housing.
ECO4 Flex is worth exploring even if you think you will not qualify through the main route. Contact your council's energy or housing team to ask. Some councils are proactive about identifying eligible households, while others require you to approach them.
Use our grant eligibility checker to see which funding routes are available to you.
Check eligibility before paying for insulation
If there is any chance you qualify for ECO4, check before paying for insulation yourself. DIY loft insulation costs £300 to £600, but ECO4 covers it for free including professional installation. The same applies to solid wall insulation, which costs £4,000 to £22,000 at full price.
What measures does ECO4 cover?
ECO4 takes a whole-house approach. An assessor visits your property, identifies all the improvements needed, and the installer carries out the full package. Here is what the scheme can fund.
| Measure | Typical value | EPC impact |
|---|---|---|
| Loft insulation (to 270mm) | £400 to £800 | +5 to 15 points |
| Cavity wall insulation | £400 to £1,500 | +10 to 15 points |
| Solid wall insulation (internal) | £4,000 to £14,000 | +10 to 15 points |
| Solid wall insulation (external) | £8,000 to £22,000 | +10 to 15 points |
| Underfloor insulation | £500 to £2,500 | +3 to 8 points |
| Flat roof insulation | £1,000 to £3,000 | +5 to 10 points |
| Room-in-roof insulation | £1,500 to £4,000 | +5 to 10 points |
| Boiler replacement (condensing) | £2,000 to £3,500 | +10 to 20 points |
| Heating controls upgrade | £150 to £350 | +3 to 7 points |
| First-time central heating | £3,000 to £5,000 | +15 to 30 points |
Values represent what the measures would cost at market rates. ECO4 covers the full cost for eligible households. EPC impacts are approximate.
The "fabric first" principle means the installer must address insulation before replacing heating systems. You cannot get a free boiler through ECO4 without also insulating the property, because a new boiler in a draughty house wastes most of its potential savings.
ECO4 does not currently cover solar panels, heat pumps (these fall under the separate Boiler Upgrade Scheme), double glazing, or draught-proofing as standalone measures.
How much can you save?
The annual savings depend on which measures are installed and your property type. Here are typical figures for a 3-bed semi-detached house on gas heating.
| Measure | Annual saving |
|---|---|
| Loft insulation (0 to 270mm) | £215 |
| Cavity wall insulation | £295 |
| Solid wall insulation | £340 |
| Condensing boiler (replacing old non-condensing) | £200 to £400 |
| Heating controls | £75 to £120 |
| Full package (insulation plus boiler) | £500 to £900 |
Source: Energy Saving Trust. Based on gas heating at Ofgem Q1 2026 rates. Savings for a 3-bed semi.
A full ECO4 package of loft insulation, cavity wall insulation, and a boiler upgrade could save a typical household £500 to £900 per year. Over the 15 to 20 year lifespan of these measures, that is £7,500 to £18,000 in reduced energy bills, all funded at no cost to you. Use our insulation savings calculator for figures specific to your property type.
How to apply for ECO4
There is no single government application form. The process works through installers and energy suppliers.
Step 1: Check your eligibility. Use our grant eligibility checker or confirm that you receive one of the qualifying benefits listed above. If unsure, contact your energy supplier or local council.
Step 2: Contact an ECO4 installer or your energy supplier. You can approach either route. ECO4 installers advertise locally and can check your eligibility directly. Your energy supplier (whoever you pay your gas or electricity bill to) can also refer you. Ask specifically about ECO4.
Step 3: Property assessment. A qualified assessor visits your home to survey its current condition, measure insulation levels, check the heating system, and determine which measures are needed. They produce a retrofit assessment based on PAS 2035 standards.
Step 4: Installation. Once approved, the installer carries out the work. This may involve multiple trades (insulation, heating, ventilation) and can take several days to several weeks depending on the scope. The installer manages the full process.
Step 5: Post-installation check. After completion, the installer should arrange a post-installation inspection and provide documentation including any warranties. A new EPC should be commissioned to confirm the improvement.
Watch out for ECO4 scams
Never pay an upfront fee for ECO4 work. The scheme is free for eligible households. Be cautious of cold callers or door knockers claiming to offer "government-funded" improvements and asking for deposits. Legitimate ECO4 installers will verify your eligibility before starting work and will not ask for payment. Check any installer on the TrustMark register.
ECO4 for landlords
ECO4 is primarily aimed at owner-occupiers and social housing, but private rental properties can qualify if the tenant receives qualifying benefits. The landlord must consent to the work and may be required to contribute to the cost, depending on the installer and the measures involved.
For landlords facing minimum EPC requirements, ECO4 can significantly reduce the cost of reaching Band E or better. If your tenant qualifies, the scheme could fund solid wall insulation or a boiler upgrade that would otherwise cost thousands.
Landlords can also access the separate Boiler Upgrade Scheme for heat pump installation, and benefit from 0% VAT on insulation and renewable energy measures until March 2027.
ECO4 Flex: the council referral route
ECO4 Flex was introduced to help households who are fuel-poor but do not receive qualifying benefits. Under Flex, your local council can declare you eligible based on local criteria. Common Flex eligibility includes:
Low income, high costs: Your household income is below a council-set threshold and your energy costs are disproportionately high relative to income. Many councils use the fuel poverty definition (spending more than 10% of income on energy).
Low EPC rating: Your property is rated E, F, or G, regardless of your income. Some councils offer Flex referrals to any household in a very energy-inefficient home.
Vulnerability: You or a household member has a health condition made worse by cold housing, such as cardiovascular disease, respiratory conditions, or limited mobility. A GP letter may be required.
Flex criteria vary significantly between councils. Some are generous and actively promote the scheme. Others have minimal Flex programmes. It is always worth asking. Contact your council's housing or environmental health team.
Quality standards and what to expect
All ECO4 work must comply with PAS 2035, the UK standard for retrofitting domestic buildings. This means a qualified retrofit assessor must survey your property before work begins, a retrofit coordinator must oversee the project, and all installers must be TrustMark registered.
In practice, quality varies. Some installers deliver excellent work. Others cut corners, particularly on ventilation (which must be addressed when insulating a property to prevent condensation problems). Here is what to look for:
Before work starts: You should receive a clear explanation of what will be installed, how long it will take, and what disruption to expect. The assessor should check for damp, asbestos risk, and ventilation needs. If they do not mention ventilation, ask. See our guide on loft insulation lifespan for understanding material quality.
During installation: Workers should protect your home, clean up daily, and communicate about progress. Loft insulation should reach 270mm. Cavity wall insulation should fill all cavities evenly. Wall insulation should include a vapour control layer where required.
After completion: You should receive a handover pack with details of what was installed, any warranties, and care instructions. A new EPC should be arranged. If you are not satisfied with the work, raise concerns immediately with the installer and, if unresolved, contact TrustMark's dispute resolution service. See recommended thermal imaging cameras to verify insulation coverage after installation.
What happens after ECO4 ends?
ECO4 closes in December 2026. The government is expected to introduce a successor scheme, but details have not been confirmed. Previous ECO schemes have run continuously since 2013, suggesting some form of obligation will continue.
If you think you might qualify, apply now rather than waiting. Installer capacity tightens as scheme deadlines approach, and there is no guarantee the successor will offer identical coverage. The measures installed under ECO4 will continue saving you money for 20 to 40+ years regardless of future scheme changes.
Other grants and funding
ECO4 is not the only funding available. Depending on your circumstances, you may also qualify for:
Boiler Upgrade Scheme (BUS): £7,500 towards an air source heat pump, available to all homeowners replacing fossil fuel heating. Read our full BUS guide. This can be combined with ECO4 insulation.
0% VAT on energy efficiency measures: Insulation, solar panels, and heat pumps installed in residential properties qualify for 0% VAT until March 2027. This applies even if you are paying for the work yourself.
Warm Home Discount: A £150 annual discount on your electricity bill, available to Pension Credit recipients and some other low-income households. This is separate from ECO4 and applied automatically by your supplier.
Use our grant eligibility checker to see all available funding for your situation. If you are considering a heat pump alongside ECO4 insulation, our heat pump calculator shows the combined cost after all grants.
Making the most of ECO4 improvements
Once your home has been insulated and upgraded through ECO4, a few additional steps maximise the benefit.
Get a new EPC. The improvements will significantly change your rating. A new EPC documents this, which matters if you sell or rent the property. Use our EPC improvement planner to estimate your new rating.
Learn your heating controls. Many households have the right equipment but use it inefficiently. If you received new heating controls, spend time understanding the programmer and thermostat. See recommended smart thermostats if you want to upgrade further.
Monitor your energy usage. See recommended energy monitors to track the real impact of your upgrades on consumption. Compare your bills before and after to confirm the savings are materialising. Check our average energy bills guide to benchmark against typical households.
Address remaining heat loss. ECO4 may not cover everything. Draught-proofing (see recommended draught excluder strips), secondary glazing, and chimney balloons are cheap additions you can do yourself to squeeze out further savings. Read our guide to improving your EPC rating for the full list of options.
Frequently asked questions
What is the ECO4 scheme?
ECO4 is a government scheme requiring large energy suppliers to fund free insulation and heating upgrades for eligible UK households. It runs until December 2026. Check our grant eligibility tool to see if you qualify.
Who qualifies for free insulation under ECO4?
Households receiving means-tested benefits (Universal Credit, Pension Credit, Child Tax Credit, and others) with a property rated D, E, F, or G. ECO4 Flex extends eligibility through council referrals for low-income households not on benefits.
What does ECO4 cover?
Loft insulation, cavity wall insulation, solid wall insulation, underfloor insulation, boiler replacements, heating controls, and first-time central heating. The scheme takes a "fabric first" approach, prioritising insulation before heating.
How do I apply for ECO4?
Contact an ECO4 installer or your energy supplier directly. There is no single government form. Your local council can also refer you through ECO4 Flex. Use our grant checker as a starting point.
When does ECO4 end?
December 2026. A successor scheme is expected but not confirmed. Apply now rather than waiting, as installer availability decreases closer to the deadline.
Data sources
ECO4 scheme details from GOV.UK. Scheme administration from Ofgem. Savings data from Energy Saving Trust. Installer standards from TrustMark.