Who is eligible for an ECO4 boiler grant?

Eligibility runs through several routes. The Help to Heat Group, Social Housing, local authority Flex, In-Fill and Supplier Flex are the recognised paths into the scheme³. The Help to Heat Group route turns on receipt of a listed benefit by the householder or another occupant of the property⁴. Flex lets a participating local authority refer owner-occupiers and private tenants it considers to be living in fuel poverty, on a low income, or vulnerable to the effects of living in a cold home⁵.

The practical answer for most households is that a low EPC rating helps. ECO4 is targeted at households with low Energy Performance Certificate ratings, and grants are awarded based on how big the difference is between the energy performance ratings⁶. Homes with an EPC of D or below may receive heavily discounted or free insulation, green heating systems or an upgraded boiler⁷.

What ECO4 is and what it funds

ECO4 is the fourth phase of the Energy Company Obligation, delivered by obligated energy suppliers and their installers rather than by a single national application. Ofgem's guidance for supplier administration describes the scheme as covering the installation of insulation and heating qualifying actions, and confirms it will run until 31 December 2026². Council pages describe the same scope in plainer terms: ECO funding pays for energy efficiency measures such as heating improvements and insulation to be installed⁹.

The measures table is broader than the phrase "boiler grant" suggests. It lists boiler upgrades to non-renewable and renewable heating systems, repair of a broken heating system, replacement of a broken efficient heating system, first time central heating, electric storage heater upgrades and repairs or replacement, connection to a district heating system, heating controls, solar PV, wall, roof, floor and loft insulation, draught proofing, window glazing and higher performance external doors¹⁰. Ofgem notes that for heating measures in particular, including heating controls and solar PV, the delivery guidance contains additional eligibility rules not covered by the measures table¹⁰.

Flex routes can fund a similar spread. Examples given by a Welsh local authority include solid wall insulation, cavity wall insulation, room in roof insulation, loft insulation, flat roof insulation, electric storage heater upgrade, first time central heating to air source heat pump, boiler upgrade from oil, LPG and solid fuel to air source heat pump, and solar photovoltaic panels¹¹.

One funding rule matters for anyone stacking schemes. Funding for measures delivered under ECO4 must not be blended with funding from other government schemes or grants, including but not limited to the Warm Home Discount, the Boiler Upgrade Scheme, the Social Housing Decarbonisation Fund and the Home Upgrade Grant¹². Funding from the Boiler Upgrade Scheme and ECO cannot be blended for the same measure or be included within an ECO4 project¹³. The two schemes are alternatives for a given measure, not partners.

Who qualifies: benefits, income and property criteria

The benefit route is the best documented. The householder, or one of the occupants residing at the property, must be in receipt of one of the listed benefits: income-based Jobseeker's Allowance, income-related Employment and Support Allowance, Income Support, Pension Credit Guarantee Credit, Working Tax Credit, Child Tax Credit, Universal Credit, Housing Benefit, Pension Credit Savings Credit and Child Benefit⁴. Housing Benefit appears on that list, so a household receiving it can qualify through the Affordable Warmth route⁸.

Benefits are not the only door. ECO4 Flex allows local authorities to identify and refer consumers living in private tenure properties who are considered low income, fuel poor, or vulnerable to the effects of living in a cold home¹⁴. Councils have published Flex routes that allow households without benefits to qualify for help if they meet income, EPC rating or health vulnerability criteria¹⁵. Independent guidance makes the same point from the household side: the scheme can also apply to people on higher incomes but with health issues, those claiming certain government benefits, or those meeting other criteria¹⁶.

Property criteria sit alongside the personal ones. ECO4 is available for private owner occupiers and private rented properties which meet the necessary eligibility criteria¹⁷. A council operating a Flex scheme states that applicants must be living in its area and be a homeowner, private tenant or landlord¹⁸. A local authority can refer owner-occupiers and private tenants it considers to be in fuel poverty or on a low income and vulnerable to the effects of living in a cold home⁵.

The boiler grant cap: £5,000 per household

The figure most often quoted for ECO4 boilers is not a payment. In ECO4, the number of available boiler grants has been capped at 5,000⁷. That is a ceiling on how many boiler grants the scheme will support in total, not a sum a household receives, and it is the reason boiler measures under ECO4 are described as limited rather than open-ended.

The £5,000 figure that circulates in searches belongs to a different scheme. The Boiler Upgrade Scheme sets a grant of £5,000 for biomass boilers in limited circumstances, and £5,000 towards a biomass boiler appears in the approved grant categories and values¹⁹. Independent guidance states that households may be able to access a grant of up to £2,500 for air-to-air heat pumps under that scheme²¹. These are Boiler Upgrade Scheme values, and they cannot be blended with ECO4 funding for the same measure¹³.

For ECO4 itself, no published per-household boiler amount exists in the scheme rules. What a home receives depends on the improvement in its energy performance rating and the cost of the measures installed, which is why two neighbouring properties can receive different packages. The cap of 5,000 boiler grants is the only headline number the scheme attaches to boilers⁷.

Homeowners and private renters: who can apply

Owner-occupiers are the straightforward case. ECO4 is available for private owner occupiers and private rented properties which meet the necessary eligibility criteria¹⁷, and Flex routes are built around owner-occupiers and private tenants⁵.

Private renters can be included, with conditions. A privately rented house must have an energy efficiency rating of E, F or G to be eligible, and the owner's permission is required⁸. Flex route one for the private rented sector covers EPC bands E to G¹¹, and a second Flex route covers EPC bands E to G for both owner-occupied and private rented sector households that meet at least two of the published proxies¹¹. Private rented sector properties occupied by a member of the Help to Heat Group, or a person declared eligible by the local authority, are covered at SAP ratings E, F and G¹⁰.

Landlords face a narrower path for heating. Private landlords can only access ECO to replace an old heating system with a renewable heating system if the existing EPC is E, F or G²². A like-for-like fossil fuel boiler swap is not the route open to a private landlord under ECO.

Social housing is a separate route within the scheme rather than part of the private tenure rules³. Households in social housing should look at the scheme's social housing path and at the Warm Homes: Social Housing Fund rather than at the private tenure criteria above.

How eligibility is assessed: financial situation and energy efficiency

Assessment has two halves. The first is the household: benefit receipt through the Help to Heat Group⁴, or a local authority decision under Flex that the household is low income, fuel poor, or vulnerable to the effects of living in a cold home¹⁴. ECO4 allows local authorities to identify the most vulnerable households who could benefit from energy efficiency improvements⁸, and the Flex component lets them identify and refer consumers in private tenure properties¹⁴.

The second half is the property. ECO4 is targeted at households with low Energy Performance Certificate ratings⁶, and grants are awarded based on how big the difference is between the energy performance ratings⁷. A home with a very poor rating has more room for improvement, which is what the scheme is paying for. Homes with an EPC of D or below may receive heavily discounted or free insulation, green heating systems or an upgraded boiler⁷.

In practice a household can expect the following sequence:

1. Check whether anyone in the home receives a listed benefit⁴.
2. If not, check whether the local authority operates a Flex route and meets its published criteria¹⁵.
3. Establish the property's EPC rating, since private rented homes normally need E, F or G⁸.
4. Approach a participating supplier, or wait for a local authority referral through Flex¹⁴.

Installation standards apply to the work itself. Where the installer is working on gas boilers, they must be Gas Safe registered²³.

What happens if my home has a poor energy rating?

A poor rating is the condition the scheme is designed around, not a barrier. ECO4 is targeted at households with low Energy Performance Certificate ratings⁶, and the size of the grant is tied to the size of the improvement in the rating⁷. A home at EPC D or below is the group most likely to receive heavily discounted or free insulation, green heating systems or an upgraded boiler⁷.

The rating also decides which measures are possible. Private rented sector properties at SAP ratings E, F and G are covered where the occupant is in the Help to Heat Group or has been declared eligible by the local authority¹⁰. Private landlords replacing an old heating system with a renewable one need an existing EPC of E, F or G²². Where a home already sits at a higher band, the improvement available is smaller and the case for a boiler measure weakens.

For a household, the energy independence question is straightforward. ECO4 work is funded by supplier obligation rather than by the household, so it reduces reliance on purchased gas or electricity for the same comfort level, and it does so without a loan or a repayment attached to the property. What remains is the grid connection and the supplier relationship: the home still buys its energy, and the measures reduce how much of it is needed rather than removing the need altogether.

Applying, and where ECO4 sits among the grants

ECO4 has no single national application form. Households can apply through specific energy suppliers, and can do so even if they are not a customer of that supplier¹⁹. The alternative is a local authority referral through Flex, where the council identifies and refers households in private tenure that meet its criteria¹⁴. Councils publish their own Flex pages and criteria, so the route differs by area.

Because ECO4 ends on 31 December 2026², timing matters for anyone weighing it against other support. The scheme cannot be combined with the Boiler Upgrade Scheme for the same measure¹³, and ECO4 funding must not be blended with other government schemes or grants including the Warm Home Discount, the Boiler Upgrade Scheme, the Social Housing Decarbonisation Fund and the Home Upgrade Grant¹². A household choosing between a supplier-funded boiler measure and a heat pump grant is choosing between two separate funding routes, not stacking them.

For the wider picture of what is open and what has closed, the Home Energy Grants and Schemes in the UK: The Full Guide sets out the current landscape. Households weighing a supplier-funded boiler against a heat pump grant can compare them directly in Boiler Upgrade Scheme vs ECO4, and those whose local authority runs a Flex route can read more in ECO4 Flex: Local Authority Flexible Eligibility. The benefit list in full is set out in What benefits qualify for ECO4 funding?, and the narrower question of a fully funded replacement is covered in Can I get a free boiler grant under ECO4?.