What ECO4 Actually Is
ECO4 stands for Energy Company Obligation phase 4, in case you’re coming to this cold. It’s the scheme that obliges the UK’s biggest energy suppliers to pay for efficiency upgrades in households that need them, insulation, boiler swaps, heat pumps, that sort of thing. It launched back in April 2022 with a four year run planned from the outset.
Pull back further and the scale of this becomes clearer. The wider ECO scheme has been going since 2013, and across that time roughly 4.4 million measures have gone into 2.6 million homes. Just under ECO4, the figure sits at around 949,800 measures across approximately 280,100 households, as of September 2025.
Why Extend It for Nine Months
This extension isn’t a scope change. Suppliers are still working to the same delivery targets they always were, they’ve simply been handed more time to reach them. The government’s own framing is that this is about winding the scheme down properly rather than cutting it off abruptly and leaving suppliers and installers in a scramble.
A couple of details get misread often enough that they’re worth spelling out plainly. Delivery targets haven’t gone up, and nothing carries over past 31 December 2026, once that date arrives, ECO4 is finished. Separately, the Great British Insulation Scheme hasn’t been given the same treatment. That one still closes at the end of March 2026 exactly as planned, and it’s a distinct scheme on its own timeline, not tied to ECO4’s extension at all.
What Happens Once ECO4 Ends
Here’s where a lot of people get caught out. There’s no direct successor supplier obligation scheme lined up to take over once ECO4 closes.
What has been confirmed is an extra £1.5 billion committed to the Warm Homes Plan, with the Warm Homes Local Grant expected to become the main route for low income households from that point. The delivery model changes too, shifting from private installers toward local councils.
That’s not a minor administrative tweak. Going through an approved installer under ECO4 tends to be quick and reasonably consistent wherever you are. Once councils are running things, expect more regional variation, in speed, in process, possibly in what’s actually available depending on where you live.
Should You Apply Now, or Hold Off
If you’re likely to qualify, applying sooner rather than later makes sense. The scheme is active, money is still being allocated, and the installer route is well worn at this stage.
Waiting isn’t without risk, though. Supplier quotas can fill up before the December 2026 deadline even arrives, and nobody’s guaranteeing the council led grant will match ECO4 for speed or accessibility once the handover happens.
Who Can Actually Apply
ECO4 runs across England, Wales and Scotland. Most people qualify through certain means tested benefits, though there’s a separate route for households that don’t claim benefits but still fall under the income threshold.
That route is called LA Flex, Local Authority Flexibility. Local councils can refer households into ECO4 using their own criteria, and a gross household income under £31,000 a year is a common benchmark. It exists precisely because plenty of people struggling with heating costs aren’t on a qualifying benefit, so if that’s your situation, a call to your local council is worth making.
The Bigger Picture
Energy costs haven’t exactly dropped out of the headlines, and Ofgem’s price cap changes in late 2025 pushed bills up further for households already dealing with old boilers or thin insulation.
The extension buys breathing room for households still weighing up whether to apply and for the installers and councils working through what’s already in the pipeline. It’s also settled some nerves in the sector itself. Before this was confirmed, a number of installers were wary of investing in training or new hires without knowing whether the work would still be there in twelve months. Having a fixed end date, even one that closes the door eventually, is a better position than the uncertainty that came before it.
The Bottom Line
Has ECO4 been extended? Yes, from 31 March 2026 to 31 December 2026, and that’s confirmed. Scope and targets stay the same. What changes is what comes after, with support moving toward councils and the Warm Homes Plan rather than ECO4 simply continuing in its current shape.
If checking your eligibility is something you’ve been putting off, this extension gives you a real window to sort it. Just don’t treat that window as permanent.
