ECO4 Energy Company Obligation UK 2026

The Energy Company Obligation (ECO) is a UK government scheme that requires large energy suppliers to fund energy efficiency measures for low-income households. The current phase, ECO4, started 1 April 2022 and was extended in January 2026 to a new end date of 31 December 2026. No ECO5 successor has been announced as of May 2026.

What ECO4 funds

ECO4 focuses on whole-house retrofit, prioritising the worst-performing homes. Funded measures can include:

• Insulation: loft, cavity wall, solid wall, room-in-roof, underfloor
• Heating upgrades: gas boiler replacement (limited circumstances), first-time central heating, air source heat pump
• Solar PV (in some delivery routes)
• Heating controls: smart thermostats, weather compensation
• Repairs: heating system repair where it would lift fuel poverty

The exact package depends on the property's current EPC, the household's eligibility route, and the supplier's prioritisation. ECO4 emphasises packages that achieve a minimum EPC improvement (typically from D/E/F/G up to C or better).

Eligibility

You can qualify via the Help to Heat Group if you meet any of:

• You receive certain means-tested benefits:
  • Income-based Jobseeker's Allowance (JSA)
  • Income-related Employment and Support Allowance (ESA)
  • Income Support
  • Pension Credit (Guarantee Credit)
  • Working Tax Credit / Child Tax Credit (within income thresholds)
  • Universal Credit
  • Housing Benefit
  • Pension Credit (Savings Credit) — limited circumstances
  • Child Benefit (within income thresholds)
• You receive a Warm Home Discount Core Group rebate, OR
• You're identified via ECO4 Flex by your local authority — local authorities can extend eligibility to households not on the standard benefits list if they're judged to be in fuel poverty

Plus the property must be EPC band D, E, F or G — homes already at C or better aren't usually eligible.

How to apply

1. Contact your energy supplier — they administer ECO4 funding (British Gas, EDF, OVO, E.ON Next, Octopus, Scottish Power, SSE all participate)
2. Or contact your local authority to ask about ECO4 Flex if you're not on the standard benefits list
3. Or use the GOV.UK 'Find a grant' service to be routed to a participating supplier
4. An assessor visits to confirm eligibility, EPC band, and recommended measures
5. The supplier appoints accredited installers to do the work
6. You don't pay; the supplier funds the install via their ECO obligation

Be wary of unsolicited "ECO4 grant" sales calls — energy suppliers don't typically cold-call. Several scams operate in this space; if you're unsure, contact the supplier directly through their main number.

ECO4 vs Warm Homes: Local Grant

Both schemes target low-income households, but the funding source differs:

• ECO4: funded by an obligation on large energy suppliers — paid for via energy bills, not Treasury
• WHLG: funded directly by Treasury and delivered via local authorities

You can typically use one or the other for any specific measure, not both. WHLG and ECO4 sometimes work together where one funds insulation and the other funds the heat pump or boiler.

What happens after ECO4?

As of May 2026, there is no ECO5 successor announced. The Warm Homes Plan, published 21 January 2026, signals a shift towards Treasury-funded local-authority-delivered schemes (WHLG and the Warm Homes Fund) rather than supplier-obligation schemes.

The Great British Insulation Scheme that ran alongside ECO4 will also not be extended — orderly closure is the policy direction.

What ECO4 means for installers and supply chains

From a homeowner's perspective, the practical impact is that ECO-funded retrofit installer capacity is concentrated on ECO4-eligible properties through 2026, and may shift to other schemes (WHLG, BUS) from 2027 onwards. If you're an owner-occupier outside the ECO4 eligibility criteria, the Boiler Upgrade Scheme and 0% VAT remain your primary public-funded routes for heat pump and energy-saving measures.