Version 5 of the Boiler Upgrade Scheme installer guidance applies to applications properly made on or after 28 April 2026, replacing V4.2, which applied from 8 May 20241. Ofgem published the summary of updates in April 20261. The Department for Energy Security and Net Zero amended the regulations governing the scheme, and those changes came into force on 28 April 20262.
The scheme has been extended to 2030, replacing the V4.2 statement that it ran to 20281. A new grant of £2,500 has been added for air-to-air heat pumps, with technology rules covering their eligibility1. From 28 April 2026, exhaust air-to-water heat pumps are eligible for the £7,500 grant2. The 2025/26 budget is £295m1. Grant values under the scheme are:
| Technology | Grant |
|---|---|
| Air-to-water heat pumps and ground source heat pumps | £7,5002 |
| Air-to-air heat pumps (residential properties only) | £2,5002 |
| Biomass boilers (limited circumstances) | £5,0002 |
From 28 April 2026, properties are no longer required to have a valid EPC to apply, but where an EPC exists the certificate number must be provided1. For properties without a valid EPC, installers must provide evidence such as a utility bill or fuel receipt, photos, or an expired EPC number if available, with case-by-case alternatives possible1. BUS heat pumps may be installed alongside supplementary heating appliances, provided those appliances are not fossil-fuel-based1. Biomass boilers may be retained or installed alongside a BUS-funded heat pump as supplementary but cannot be used to meet the heating demand requirement1. The heat pump must still be sufficient on its own for space heating1.
Installers must pass on the BUS grant as an upfront discount and must not request or accept the discounted amount from owners, described in the summary of updates as an entirely new substantive requirement1. Installers cannot use a temporary MCS certification number to create an account or apply for a voucher; retrospective applications are allowed only after full certification, at installer risk1. Under the redeveloped MCS installer scheme, installers must continue to hold membership with one of the two approved consumer codes, RECC or HIES, to deliver work under the scheme until further notice1. MCS has redeveloped its installer scheme, which will be rolled out throughout 2026 and into early 20273.
"Date reset: V5 applies to applications properly made on or after 28 April 2026 (V4.2 was “properly made on/after 8 May 2024”)"
The final date on which Ofgem can issue vouchers is 31 December 20292. Vouchers for air-to-water heat pumps, air-to-air heat pumps and biomass boilers are valid for 3 months; ground source heat pump vouchers are valid for 6 months2.
Why it matters for households
The Boiler Upgrade Scheme pays the grant to the installer, who applies it as an upfront discount, so the amount a household sees is the discounted quote rather than a payment received later4. The removal of the standing EPC requirement changes who can apply: homes that previously fell short on that criterion are no longer excluded on that ground alone, though an existing certificate number must still be supplied where one exists1. The grant amounts now include a lower-value route for air-to-air heat pumps, which are eligible in residential properties only2. Households that keep a non-fossil-fuel supplementary appliance alongside a BUS-funded heat pump are permitted to do so, but a fossil-fuel system cannot be kept alongside a BUS-funded installation1. For a home's energy independence, the practical effect is that the funded heat pump must be sized to meet full space heating demand on its own, so the grant does not support a system that leans on a retained boiler for part of the load1. Eligibility remains limited to properties in England and Wales, and social housing is not eligible2. The eligibility rules and the application process are installer-led; a household cannot apply directly4.
What happens next
From 21 July 2026, uplifted grant values will be available to eligible off-gas grid properties5. The uplifted grant is £9,000 for air-to-water or ground source heat pumps in off-gas grid properties replacing a heating system fuelled by oil or liquefied petroleum gas, and will be in place until 31 March 20272. On 28 May 2026, the Secretary of State published a grant change notice confirming the new set of grant categories and values effective from 21 July 20262. Version 5.1 of the property owner guidance is the current version and applies to applications properly made on or after 28 April 2026, with the uplifted grant updates applying to applications properly made on or after 21 July 20265. Version 5 of the property owner guidance has been removed5.
Sources5 cited
- Boiler Upgrade Scheme Summary of Updates in the Boiler Upgrade Scheme Installer Guidance version 5, ofgem.gov.uk
- Boiler Upgrade Scheme Installer Guidance V5.1, ofgem.gov.uk
- Boiler Upgrade Scheme Installer Guidance, ofgem.gov.uk
- Boiler Upgrade Scheme: Property owner guidance V4, ofgem.gov.uk
- Boiler Upgrade Scheme: Guidance for Property Owners | Ofgem, ofgem.gov.uk