The government expects to undertake a comprehensive assessment of the MCS Customer Commitment in early 2026 before recognising it as a code of practice for the Boiler Upgrade Scheme, according to its response to Part 1 of the consultation on the scheme, published in November 20251. The commitment is a consumer protection element of the redeveloped installer scheme run by MCS, the Microgeneration Certification Scheme2.
The government response states that it will "assess the Microgeneration Certification Scheme (MCS) Customer Commitment as a consumer code before determining whether to approve it for the scheme"1. MCS, which describes itself as the sole certification scheme for clean heat measures under the BUS, said the Department for Energy Security and Net Zero (DESNZ) "has stated that it will assess the effectiveness of the MCS Customer Commitment, before approving it for the Boiler Upgrade Scheme in early 2026"2. The government response puts the timing as "early 2026, subject to the status of reform implementation"1.
Until approval, installers delivering BUS installations must retain Consumer Code membership, MCS said, adding that it anticipates a quick approval process after which that requirement will be dropped2. Once the commitment is approved, installers would need either the Customer Commitment or Consumer Code membership to deliver installations under the BUS2. MCS also said all installers will need to comply with the commitment from the point of certification under the redeveloped scheme2.
"We expect to undertake this assessment in early 2026, subject to the status of reform implementation."
The consultation ran from 30 April 2025 to 11 June 2025 and drew 357 responses, of which 68 came from installers, 32 from manufacturers, 17 from trade associations, 21 from non-governmental organisations, 83 from private individuals and 136 from other respondents1. The response document also sets out other changes: grants of £2,500 for air-to-air heat pumps, grants of £2,500 for heat batteries once standards are in place, relaxation of the Energy Performance Certificate requirement from 2026/27, and a requirement for installers to deduct the grant from upfront costs1. MCS said applications for heat battery installations are anticipated to open during 2026/272.
| Change | Detail | Timing |
|---|---|---|
| Air-to-air heat pump grants | £2,500 per installation | From 2025/26, subject to Parliament1 |
| Heat battery grants | £2,500 per installation | Once standards in force; applications anticipated 2026/271 |
| EPC requirement | Relaxed, valid EPC still required at application where one exists | From 2026/271 |
| Grant deduction | Installers to deduct grant from upfront costs | Regulations to be introduced1 |
| MCS Customer Commitment | Assessed as a consumer code | Early 20261 |
The government response also states that further work is needed on third-party ownership of BUS-funded heating systems before determining eligibility, citing complex interactions with the current regulatory landscape1. It says it will continue to work with industry, the FCA, HM Treasury and other stakeholders on whether such models are viable within the regulatory framework1. On contract durations, the response records that these "should not exceed the expected lifespan of a heat pump, typically 15 to 20 years", with a few respondents proposing shorter caps of 10 to 15 years or alignment with warranty periods of around 5 to 6 years1.
Why it matters for households
The MCS Customer Commitment sits alongside the grant rules as a consumer protection layer for anyone using the BUS to part-fund a heat pump. If it is approved as a code of practice, the route by which an installer can deliver a BUS-funded installation changes: membership of the commitment would substitute for Consumer Code membership2. For a household, the practical effect is on which installers can carry out grant-funded work and on the protections attached to that work, rather than on the grant amounts themselves. The other confirmed changes affect what a home can claim for and when: air-to-air heat pumps and heat batteries each attract £2,500, and the EPC requirement is relaxed from 2026/27, though a valid EPC will still be required at the point of application for properties where one already exists1. The grant deduction requirement means the £7,500 hydronic heat pump grant, or the relevant amount for other technologies, is taken off the upfront cost rather than reclaimed later1. Third-party ownership models, where a household does not own the heating system, remain outside the scheme pending further work, so their eligibility has not been determined1.
What happens next
The assessment of the MCS Customer Commitment is expected in early 2026, subject to the status of reform implementation1. MCS said it is reviewing timelines in light of the announcement and will provide a further update in the coming weeks2. The government response says changes will begin to be introduced during 2025/26, subject to the will of Parliament, with implementation timelines varying by legislative amendment and operational complexity1. Further detail and coming into force dates for the EPC relaxation and the grant deduction requirement will be set out2. The BUS will continue to 2029/30 with rising annual budgets, with further budget details to be provided in due course1.
Sources2 cited
- Part 1: Amendments to the Boiler Upgrade Scheme - government response, assets.publishing.service.gov.uk
- MCS welcomes changes to Boiler Upgrade Scheme - MCS, mcscertified.com