Can I get the BUS grant without PAS 2035

No. The Boiler Upgrade Scheme requires MCS certification on the installer, but does not currently mandate PAS 2035 framework engagement for a standalone heat-pump install. PAS 2035 becomes mandatory the moment another publicly funded measure (ECO4, GBIS, SHDF, HUG, Warm Homes Plan) is layered onto the same project.

What conditions actually apply for BUS?

Owner-occupier or private rented property in England and Wales; an MCS-certified installer; a fossil-fuel system being replaced. Since the 28 April 2026 amendment there is no EPC precondition and no insulation-recommendation barrier; where no EPC exists the installer evidences the current fuel another way (utility bill plus photos of the existing system).

When does PAS 2035 become mandatory?

ECO4, GBIS, Social Housing Decarbonisation Fund, Home Upgrade Grant, and the forthcoming Warm Homes Plan all require PAS 2035 framework engagement (Assessor, Coordinator, MTIP, post-install monitoring). Any project pulling on those grants must follow the framework.

What does that mean for cost?

An installer-led BUS-only project saves £2,500 to £6,000 in PAS 2035 process fees but transfers the design and sequencing risk to the homeowner. A PAS 2035 project carries the process fee but transfers the same risk to a TrustMark-lodged Coordinator.