What does eco4 cover?

The Energy Company Obligation (ECO4) covers free or heavily subsidised energy-efficiency upgrades for low-income and vulnerable households in England, Scotland and Wales, including insulation, heating systems and renewable technologies, with a total value of up to £25,000 per property depending on eligibility (GOV.UK, 2026).

ECO4 is not a cash grant you receive; instead, energy suppliers fund and install the measures directly through approved installers. The scheme targets homes with an Energy Performance Certificate (EPC) rating of D, E, F or G, and focuses on the most cost-effective upgrades first. It applies to owner-occupied homes, private rented properties (with landlord permission) and some social housing. You must be receiving a qualifying means-tested benefit, or be referred via a local authority’s flexible eligibility route. ECO4 runs until March 2026, with a final deadline for installations of 31 March 2026 (Ofgem, 2026).

Insulation and heating systems

ECO4 covers cavity wall insulation, loft insulation, solid wall insulation (internal or external), floor insulation and flat roof insulation. For heating, it includes replacement boilers, heat pumps (air source and ground source), electric storage heaters and district heating connections. The scheme prioritises fabric-first improvements, insulation before heating, to reduce heat loss. A typical solid wall insulation installation can cost £8,000–£15,000, fully covered under ECO4 for eligible households (Energy Saving Trust, 2026). Gas boiler replacements are only available if no mains gas is present or if the existing boiler is broken beyond repair.

Renewable technologies and controls

ECO4 funds solar photovoltaic (PV) panels, solar thermal systems and heat pumps, but only after insulation measures have been installed or deemed unnecessary. A typical 3.5kWp solar PV system generates around 3,000 kWh per year, saving £300–£500 annually on electricity bills (Energy Saving Trust, 2026). The scheme also covers heating controls such as smart thermostats, programmer timers and thermostatic radiator valves. All installations must be carried out by TrustMark-registered installers and comply with Microgeneration Certification Scheme (MCS) standards for renewables (MCS, 2026).

What ECO4 does not cover

ECO4 does not cover double glazing, doors, replacement windows, new kitchens or bathrooms, or non-heating electrical work. It also excludes homes already rated EPC band A, B or C, unless a specific exception applies. For private tenants, the landlord must agree to the work and cannot increase rent to recover costs. The scheme does not cover homes in Northern Ireland, separate schemes apply there. If you have already received ECO funding since 2013 for the same measure, you may not qualify again unless the measure has failed (GOV.UK, 2026).

A worked example

A typical 1930s semi-detached home in Manchester with an EPC rating of F could receive ECO4-funded cavity wall and loft insulation plus a replacement air source heat pump, reducing annual heating bills by roughly £580. Before any grant, the total cost of these measures would be around £14,000. With full ECO4 funding covering the insulation and a significant portion of the heat pump, the homeowner pays nothing upfront if eligible through the flexible eligibility route via their local authority. The heat pump installation also qualifies for the BUS grant of £7,500, which the installer claims on the homeowner’s behalf, further reducing the supplier’s obligation cost. According to the Energy Saving Trust, a well-insulated semi-detached home can save £580 per year on heating bills after switching from an old gas boiler. The 0% VAT on heat pumps (until March 2027) adds no extra cost. Over 25 years, the total savings exceed £14,500, with the home’s EPC rising to a Band C and increasing property value.

What homeowners often get wrong

The most common mistake is assuming ECO4 provides a cash payment you can spend on any home upgrade. The scheme works differently and misunderstanding this can cost you thousands. Here are three frequent errors homeowners make.

1. Believing ECO4 is a cash grant ECO4 does not pay you money. Instead, your energy supplier arranges and pays for approved installers to fit the measures directly. If you pay a contractor yourself and then try to claim back, you will not be reimbursed and could lose the full value of the upgrade.
2. Thinking any home qualifies Only homes with an EPC rating of D, E, F or G are eligible. If your home already has a Band C or above, you cannot get ECO4 funding for insulation or heating upgrades. A quick check on the gov.uk EPC register saves time and disappointment.
3. Ignoring the flexible eligibility route Many homeowners assume they must be on a qualifying benefit to apply. Local authorities can refer households through flexible eligibility if your income is low or you have a health condition made worse by a cold home. Missing this route means you could leave £10,000 or more of free upgrades unclaimed.

Quick reference

• ECO4 covers cavity wall insulation, loft insulation, solid wall insulation, floor insulation, replacement boilers, air source heat pumps, ground source heat pumps and electric storage heaters.
• The scheme is available in England, Scotland and Wales and runs until 31 March 2026 with all installations completed by that date.
• Eligible homes must have an EPC rating of D, E, F or G and you must receive a qualifying benefit or be referred via a local authority flexible eligibility route.
• ECO4 is not a cash grant, your energy supplier pays the approved installer directly so you never handle the money yourself.
• Applying through a rogue trader who claims to handle ECO4 paperwork can void your warranty and leave you with substandard work, so always use an Ofgem-approved installer.