The government's November 2025 consultation response set out the changes to the Boiler Upgrade Scheme that were implemented in April 2026, according to Ofgem's annual report for Scheme Year 4, published in July 20261. The report covers 1 April 2025 to 31 March 2026 and states that the BUS regulations were amended, having been laid in Parliament on 25 March 2026 and coming into force on 28 April 20261.
The report describes the amendments as "introducing changes set out in the government's November 2025 consultation response"1. It also records a grant uplift: from 21 July 2026, the BUS grant increased from £7,500 to £9,000 for eligible properties that are not connected to the gas grid1. Updated guidance for installers and property owners reflecting the scheme changes was published on 2 July, ahead of applications opening on 21 July 20261. In June 2026, MCS:2025 was approved by the Secretary of State as a consumer code for BUS1.
"The BUS regulations were amended, having been laid in Parliament on 25 March 2026 and coming into force on 28 April 2026"
The report gives scheme totals from launch on 23 May 2022 to the end of March 2026. It states that 80,098 vouchers were redeemed, of which 98% were air source heat pumps, and that £560.3 million was paid to support installations1. Of all grants paid, 76.3% (61,076) were for the replacement of fossil fuelled heating systems, 10.2% were for other heating system types such as direct electric, and 13.7% were for eligible self-build properties with no previous heating system1. At the end of March 2026, 1,789 MCS certified installation companies were registered to participate in the BUS, and the top 10 installers by application volumes were responsible for over 32% of all grant applications received1.
During Scheme Year 4, Ofgem received 45,880 stage 1 applications, issued 39,435 vouchers worth over £295 million, rejected 2,645 applications that failed eligibility checks, and saw 3,301 applications withdrawn1. On compliance, the report states that 416 installations that received grant payments in 2025 to 2026 were selected for statistical audit, with an initial compliance rate for those closed of 98.52%, and that 626 targeted audits were conducted on installations identified as having a potential increased risk of non-compliance, with an initial compliance rate of 89.38%1. The value of payments made in error during 2025 to 2026 is estimated at £4.5 million, or 1.9% of total payments, within a confidence interval of £1.4 million to £7.6 million1. Ofgem closed 876 compliance investigations during Scheme Year 4, from which 367 (41.9%) applications were found to be non-compliant, and states that £1,960,000 of public funds were either protected or identified for recovery1.
| Measure | Figure |
|---|---|
| Vouchers redeemed since launch | 80,098 |
| Total paid since launch | £560.3 million |
| Stage 1 applications received, Scheme Year 4 | 45,880 |
| Vouchers issued, Scheme Year 4 | 39,435, worth over £295 million |
| Registered installers at 31 March 2026 | 1,789 |
| Payments made in error, 2025 to 2026 | £4.5 million (1.9% of total payments) |
Why it matters for households
The changes described in the report affect which homes qualify and how much support is available. The grant uplift to £9,000 applies to eligible properties not connected to the gas grid, while the report does not state a change to the £7,500 figure for properties that are connected1. Households weighing up a heat pump against other options can check the eligibility rules and the position for homes with a gas boiler. The report also confirms the scheme's extension to 2030 under the Warm Homes Plan, with total investment of around £2.7 billion and annual funding increasing over time1. For a household, that longer settlement is the main signal of continuity: the grant is not a short-term window, and the application process runs in two stages, with property owner consent required before a voucher is issued1. The compliance figures show that eligibility is checked after payment as well as before, and that funds can be recovered where rules are not met1.
What happens next
The report states that the grant uplift and the amended regulations took effect in 2026, with applications opening on 21 July 20261. It confirms the scheme's extension to 2030 under the Warm Homes Plan1. No further dated steps beyond those are set out in the report.
Sources1 cited
- BUS Annual Report 2025 to 2026, ofgem.gov.uk