Free solar panels under ECO4 are not a myth — but they are not available to everyone, and the application process is more involved than a simple online form. ECO4 (the Energy Company Obligation scheme, phase 4) is a government programme that obliges large energy suppliers to fund energy efficiency upgrades for low-income and fuel-poor households. Solar panels are one of the measures that can be funded, though they are typically approved as part of a package of improvements rather than in isolation. This guide walks you through every stage: checking eligibility, finding an approved installer, understanding the home assessment, and what to do if your application is refused.
ECO4 Eligibility: Who Qualifies for Free Solar Panels?
ECO4 has two eligibility routes. You must meet the criteria for at least one of them, and your home must also meet a property condition threshold.
Route 1: Means-Tested Benefits
You qualify under the means-tested route if you or anyone in your household receives one of the following qualifying benefits:
- Universal Credit (with a net household earnings threshold — currently under £31,000/year)
- Income-based Jobseeker’s Allowance (JSA)
- Income-related Employment and Support Allowance (ESA)
- Income Support
- Pension Credit (Guarantee Credit or Savings Credit)
- Working Tax Credit or Child Tax Credit (with household income under £31,000)
- Child Benefit (with household income under £31,000)
Route 2: ECO4 Flex (LA Flex)
Local authorities can refer households that do not receive qualifying benefits but are still considered fuel-poor or living in cold homes. This route — sometimes called ECO Flex or LA Flex — gives councils discretion to help households they identify through local data. Contact your local council’s energy efficiency or housing team to ask whether they have an active LA Flex referral scheme.
Property Condition: EPC D–G
Regardless of which eligibility route you use, your home must have a current Energy Performance Certificate (EPC) rating of D, E, F or G. The ECO4 scheme is specifically targeted at less energy-efficient homes, since these are where the carbon savings are largest. If your home is already rated A, B or C, you are unlikely to qualify. The UK Government’s EPC register lets you look up your current certificate instantly — most homes have one from a previous sale or rental.
If your EPC is out of date or you have made improvements since it was issued, a new assessment (typically £60–£120) may upgrade your rating — potentially above D, which would disqualify you. Get a new EPC only if you are confident of the outcome or if an installer advises it.
Step-by-Step: How to Apply for ECO4 Solar Panels
Step 1: Eligibility Check
Start with the Energy Saving Trust’s grants and schemes checker, which signposts ECO4 and other schemes you may qualify for. You can also check directly via the Simple Energy Advice service (now integrated into gov.uk). If you receive a qualifying benefit, gather evidence of it — a recent award letter or Universal Credit statement works well.
Step 2: Find an ECO4-Approved Installer
ECO4 work must be carried out by a MCS-certified installer who is also registered with an ECO4 scheme provider. The easiest route is to contact your energy supplier directly — all suppliers with more than 150,000 customers are obligated to fund ECO4 measures and will have a list of approved installers. Alternatively, your local council may maintain a list of approved installers under their LA Flex scheme.
Be cautious of cold calls or door-knocking companies claiming to offer “free government solar”. Legitimate ECO4 installers will not pressure you. Always verify that the installer is MCS-certified and has an active ECO4 obligation with a named energy supplier before agreeing to any assessment. Our guide to MCS-certified installers explains what questions to ask and what certification to look for.
Step 3: Initial Survey and Eligibility Confirmation
Once you have found an approved installer, they will carry out a free initial survey. This is a brief visit (typically 30–60 minutes) to assess your roof condition, confirm your property type, and verify that you meet the ECO4 eligibility criteria. They will check your benefit entitlement documentation and your EPC. At this stage, they will also assess whether solar panels alone can be approved, or whether additional measures (see below) are required as part of a package.
Step 4: Whole-House Assessment
ECO4 requires a more thorough assessment than ECO3 did. A whole-house assessment uses the SAP (Standard Assessment Procedure) methodology to calculate your home’s current energy performance and the improvement that proposed measures will achieve. The installer or a Retrofit Assessor accredited under PAS 2035 must carry this out.
The assessment looks at:
- Insulation levels (walls, roof, floor)
- Heating system type and age
- Glazing and draught-proofing
- Current EPC rating and the modelled rating after improvements
The key point: ECO4 aims to bring homes to at least EPC band C. If solar panels alone will not achieve that target, the installer may propose additional measures alongside them — most commonly loft insulation, cavity wall insulation or a first-time central heating system.
Step 5: Measures Approved and Funding Confirmed
Once the assessment is complete, the installer submits your case to the energy supplier (the ECO4 obligation holder). The supplier reviews the assessment and confirms which measures they will fund. You will receive a written confirmation of what is being installed and that it is fully funded. You should not be asked to pay anything — if you are, ask for a full written breakdown and check with your energy supplier directly.
Measures commonly approved alongside solar panels include:
- Loft insulation (top-up or first-time)
- Cavity wall insulation
- First-time central heating (replacing electric storage heaters)
- Air source heat pumps (in some cases, where the fabric is sufficiently upgraded)
- Smart heating controls
Step 6: Installation
A typical domestic solar installation takes one to two days. The installer will scaffold the roof, fit the mounting rails, attach the panels, run cables to the inverter (usually in the loft or utility room), and connect to your consumer unit. You will be asked to be present (or have someone there) for the duration. At the end, you receive your MCS certificate, a system handover walkthrough, and documentation for any warranty claims. The MCS certificate is also what you need to register for the Smart Export Guarantee.
How Long Does ECO4 Take from Application to Installation?
The timeline varies significantly depending on the installer’s workload, the complexity of the assessment, and whether additional measures are required. A realistic expectation:
- Initial contact to survey: 1–4 weeks
- Survey to assessment completion: 1–3 weeks
- Assessment to funding confirmation: 2–6 weeks
- Funding confirmation to installation: 4–12 weeks (longer if scaffolding or multiple measures are involved)
Total: typically 2–5 months from first contact to panels on the roof. If your area has high demand or limited approved installer capacity, it can take longer. The scheme has a closing date — check the current status of ECO4 on Ofgem’s ECO scheme page — and plan accordingly.
What Happens If Your ECO4 Application Is Refused?
Refusals happen for a few reasons: your home’s EPC rating may already be too high, the proposed measures may not achieve enough improvement to justify the funding, or the installer may not be able to access a willing obligation holder for your specific situation.
If you are refused, you have options:
- Try a different installer. Different installers have relationships with different energy suppliers, and some are better placed to secure funding for borderline cases.
- Apply via your local council’s LA Flex scheme if you were refused on the benefits route but may qualify on vulnerability grounds.
- Consider the Great British Insulation Scheme, which has slightly broader eligibility and funds single insulation measures rather than whole-house packages.
- Look at other solar grants. Our solar grants guide covers all the funding options currently available in the UK, including devolved schemes in Scotland and Wales.
If you are not eligible for ECO4 but are interested in solar, it is still worth running the numbers on a self-funded installation. Use our solar savings calculator to see estimated payback periods at current energy prices — many UK households find that self-funded solar pays back in 7–10 years and delivers significant lifetime savings.