Every ECO4 guide leads with the same date: the scheme closes 31 December 2026. That's true, and it's also the wrong number to plan around if you're a landlord thinking about applying.
Why the closing date isn't the deadline that matters
ECO4 applications aren't instant. Once a tenant or LA Flex referral is submitted, processing through an obligated energy supplier typically takes 10 to 18 weeks before installation happens. Work backwards from 31 December 2026 with an 18-week buffer and the safe window to start a new application closes around September 2026 — roughly three months earlier than the headline date suggests.
Because this is the scheme's final year, supplier funding is also being drawn down faster than in previous years, and installer capacity is tightening in some regions as the deadline approaches. Applying early in that window matters more than it did in earlier ECO cycles.
What's still on offer before then
ECO4 funds insulation, boiler replacements, heat pumps, and solar panels in rental properties at no cost to the landlord, provided the property and tenant meet the criteria:
- Property: EPC band D, E, F, or G (band C or above doesn't qualify — the scheme exists to lift sub-standard homes, not improve ones already at the target)
- Tenure: owner-occupied or privately rented with landlord consent
- Household: a resident receiving a qualifying means-tested benefit (Universal Credit, Pension Credit, and others), or a referral through your local council's LA Flex route if they don't
Any of the large obligated energy suppliers — British Gas, EDF, E.ON, OVO, ScottishPower, Octopus, and others — can deliver ECO4 measures, regardless of who currently supplies the property's gas or electricity.
What happens after ECO4 closes
A successor programme is expected as part of the wider Warm Homes Plan, but its eligibility criteria and funding levels haven't been confirmed. Past experience with the ECO scheme's earlier iterations is a reasonable guide here: each successive version has tended to be less generous than the one before it, not more. If a property in your portfolio is already close to qualifying, there's a real cost to waiting to see what replaces ECO4 rather than applying now.
A practical way to plan
If you have a property that might qualify, treat September 2026 as your working deadline, not December. That gives you the processing-time buffer, and it means you're applying while installer capacity is still relatively open rather than competing for slots in the scheme's final weeks.
This guide is informational and reflects scheme rules as understood in mid-2026. ECO4 eligibility, processing times, and installer capacity vary by supplier and region — confirm current specifics with an obligated energy supplier, your local authority, or GOV.UK before applying. It isn't financial or legal advice.