If you have been putting off applying for eco4, the clock is now genuinely running out. The scheme that has funded free and subsidised wall insulation for hundreds of thousands of UK households is closing its obligation period on 31 December 2026, and after that date there is no confirmed successor scheme in the same form.
What Eco4 Actually Is
Eco4 is the fourth version of the Energy Company Obligation, a government backed scheme that requires energy suppliers to fund energy efficiency measures in eligible homes. It is administered by Ofgem on behalf of the Department for Energy Security and Net Zero, and it exists to tackle fuel poverty while cutting household energy bills.
Unlike a simple grant, eco4 takes what is called a whole house approach. Instead of funding a single measure in isolation, suppliers are encouraged to install combinations of improvements together, cavity wall insulation alongside loft insulation, for example, because the combined effect on a home’s energy performance is greater than any single measure on its own.
Who Actually Qualifies for Eco4
Eligibility is based primarily on receiving certain means tested benefits, such as Universal Credit, Pension Credit, or Income Support. Alongside that, your property typically needs an EPC rating of E, F, or G, since the scheme is designed to help the least efficient homes first.
There is also a route called eco4 Flex, which allows local authorities to refer households that would not otherwise qualify under the standard criteria, provided they can show the household is in fuel poverty or vulnerable to living in a cold home. This widens who can access funding beyond strict benefit eligibility, so it is worth checking with your local council even if you are unsure whether you qualify under the main scheme.
Wall Insulation Under Eco4
Cavity wall insulation is one of the most commonly delivered measures under eco4, largely because it is quick to install and delivers a strong energy performance improvement for a relatively modest cost. For solid wall properties, where cavity fill is not an option, external or internal wall insulation can also be funded under the same scheme, alongside other structural insulation and heating measures.
Because eco4 favours a whole house approach, wall insulation is often bundled with other measures during the same assessment. If your walls and your heating system are both underperforming, a single eco4 application can address both, which is generally more cost effective than tackling them separately over time.
Why the December 2026 Deadline Matters
The eco4 obligation period was originally set to run from July 2022 to 31 March 2026. It has since been extended, and energy suppliers must now deliver all remaining qualifying measures in full no later than 31 December 2026. Ofgem’s own delivery guidance confirms this extended deadline, rather than the earlier date still mentioned in some older articles.
In practice, this means the closer you get to the end of the year, the harder it becomes to complete an application, get a survey booked, and have the work carried out in time. Suppliers have finite obligations to fulfil, and demand tends to spike as deadlines approach, so acting earlier rather than later gives you a meaningfully better chance of securing funding before the scheme closes.
What Happens After Eco4 Ends
There is no confirmed like for like successor to eco4 announced at this stage. Some support continues through the wider Warm Homes Plan, including grants and low or zero interest loans for households above the strict benefit thresholds, but the specific structure of eco4 itself is not guaranteed to continue in its current form.
This is exactly why the closing window matters. If wall insulation funding through eco4 is available to you now, waiting until the scheme’s future is clearer could mean missing the opportunity entirely. Households who might otherwise qualify should treat 2026 as the year to check eligibility, not a future one.
How to Check Your Eligibility
Because eco4 is delivered through obligated energy suppliers rather than a single central application, the fastest route is usually to check with your current energy supplier directly, or to search for eco4 Flex through your local council if you are unsure whether you meet the standard benefit criteria. A reputable installer can also carry out an initial eligibility check as part of a free survey.
If your home has solid walls rather than a cavity, it is worth understanding the cost difference before applying, since external wall insulation involves different installation requirements and a different funding pathway under eco4 than standard cavity fill.
Getting Started Before the Deadline
The safest approach is to start the eligibility check now rather than closer to the end of the year, since installer capacity tightens as suppliers rush to meet their obligations before 31 December 2026. For a full breakdown of how wall insulation works, what it costs without funding, and which method suits your property, our complete guide to wall insulation is a useful starting point.
If you think you might qualify, get in touch with our team today for an eligibility check before this year’s eco4 funding window closes for good.