In England in 2026, free cavity wall insulation is mainly available through ECO4, which ends on 31 December 2026, and the council-run Warm Homes: Local Grant, usually for households with an income of £36,000 a year or less in homes rated EPC D to G. The Great British Insulation Scheme closed on 31 March 2026; in Scotland the Home Energy Scotland grant can pay towards insulation, and in Wales the Nest scheme can provide free improvements to those who qualify.
When this guide fits
Clues worth recording
- Your home has unfilled cavity walls
- Someone in the household gets a means-tested benefit
- Your EPC rating is D, E, F or G
- You have been cold-called about “free government insulation”
Which cavity wall insulation grants are open in 2026?
In England there are two main routes. ECO4, the Energy Company Obligation, requires energy suppliers to fund energy-efficiency work for eligible households; the government’s response on extending it confirms it will end on 31 December 2026. The Warm Homes: Local Grant is run by local councils in England and covers measures including wall, loft and underfloor insulation.
The Great British Insulation Scheme ended as planned on 31 March 2026 and was not extended. If a caller offers you a place on it now, treat that as a warning sign.
Scotland and Wales have their own schemes. Home Energy Scotland says its grant can pay up to 75% of the combined cost of energy-efficiency measures such as insulation, up to £7,500, with an extra £1,500 for rural and island homes; you must own the home and live in it as your main residence, and you do not need to be on benefits. In Wales, the Welsh Government’s Nest scheme gives free advice and, for those who qualify, free improvements including insulation.
Who qualifies for ECO4?
GOV.UK says you might get help if you live in social housing, or if you live in private housing and claim one of these benefits: Universal Credit, Pension Guarantee Credit, Pension Savings Credit, Income Support, income-based Jobseeker’s Allowance, income-related Employment and Support Allowance, Child Benefit or Housing Benefit.
The home’s energy rating matters too. If you own the home it must be rated D, E, F or G; if you rent privately, or live in social housing, it must be E, F or G. There is no single application form: GOV.UK says to contact your local council to find out if it is taking part, or contact an energy supplier directly. Because ECO4 ends on 31 December 2026, ask early whether there is still time for a survey and installation.
- On a qualifying benefit, or in social housing
- EPC D to G if you own your home
- EPC E to G if you rent
- Apply through your council or an energy supplier
Who qualifies for the Warm Homes: Local Grant?
GOV.UK says the home must be in England, be privately owned (by you or your landlord) and have an EPC rating of D, E, F or G. Household income must usually be £36,000 a year or less, although you may still qualify on a higher income if you live in certain postcode areas or someone in the household gets certain benefits.
You apply online through GOV.UK or by phone, and GOV.UK says your council will usually contact you within 10 working days to arrange a home survey. If you qualify you will not need to pay for the work, although landlords may need to contribute towards some improvements.
What happens after ECO4 ends?
The government has said there will be no successor energy-supplier obligation after ECO4. Its Warm Homes Plan says low-income grant funding will be delivered initially through the Warm Homes: Social Housing Fund and the Warm Homes: Local Grant, and that from 2027/28 it intends to combine them into a single low-income scheme. For households that do not qualify for grants, the plan proposes up to £1.7 billion for new low- and zero-interest consumer loans to help with upfront costs.
The plan also says that by the end of 2024 an estimated 71% of British homes had cavity wall insulation, and that insulation measures remain a cornerstone of energy efficiency when they are installed with appropriate ventilation.
Is your home suitable for cavity wall insulation?
A grant does not decide whether a wall should be filled. The government’s consumer guide says most cavity wall insulation has been completed in suitable homes to good standards, but genuine problems have arisen where it was not. Before any installation, ask the installer to explain how they checked the wall’s condition, the cavity, and how exposed the wall is to wind-driven rain, and which guarantee provider will cover the work. Get the answers in writing.
If your walls are already filled and you are seeing damp or mould, a grant for more insulation is the wrong starting point. Find out what is causing the damp first.
How do you avoid grant scams?
The government’s cavity wall insulation guide warns about callers by phone or on the doorstep. Its advice applies just as well to grant offers: check identification and company details before letting anyone in, do not sign documents on the doorstep, do not hand over bank details, your National Insurance number or your guarantee, and ask for all charges in writing. Report anything suspicious to Trading Standards or Citizens Advice.
You can check the official routes yourself. ECO4 goes through your council or an energy supplier, the Warm Homes: Local Grant through GOV.UK and your council, and GOV.UK’s “find ways to save energy in your home” service gives property owners in England and Wales recommendations with estimated costs and savings.
What if you do not qualify for a grant?
You can still pay for cavity wall insulation privately. Ask for a written suitability check and quotation, compare more than one, and make sure the guarantee and its provider are named before work starts. If you have a problem with existing cavity insulation rather than a gap to fill, our advice library and enquiry form are set up for that.
Questions homeowners ask
What people usually want to know
Is free cavity wall insulation still available in 2026?
In England, through ECO4 until it ends on 31 December 2026 and through the council-run Warm Homes: Local Grant for eligible households. The Great British Insulation Scheme closed on 31 March 2026.
What income do I need to be under for the Warm Homes: Local Grant?
GOV.UK says household income must usually be £36,000 a year or less, though some households on higher incomes qualify through their postcode or benefits. The home must be in England, privately owned and rated EPC D to G.
Can I get a cavity wall insulation grant in Scotland?
Home Energy Scotland says its grant can cover up to 75% of the cost of insulation and other measures, up to £7,500, with £1,500 more for rural and island homes. You must own and live in the home.
What replaces ECO4?
There will be no successor supplier obligation. The Warm Homes Plan says low-income support will run through the Warm Homes grants, combined into a single low-income scheme from 2027/28, with proposed low- and zero-interest loans for other households.
Sources & review
Evidence behind this guide
Reviewed 2 October 2026. We use primary guidance where available and label trade-body advice clearly.