How Much Is the Boiler Upgrade Scheme Grant and How Long Is the Wait?
The Boiler Upgrade Scheme (BUS) offers a £7,500 grant toward an air source or ground source heat pump in England and Wales, applied for by your MCS-certified installer, with current survey-to-installation waiting times running 8–16 weeks depending on regional installer capacity in August 2026.
Grant Criteria: Who Qualifies
- Property type: Domestic properties in England and Wales with an existing fossil fuel heating system (oil, LPG, or mains gas boiler) being replaced.
- Grant value: £7,500 flat rate for both air source heat pumps (ASHP) and ground source heat pumps (GSHP) — GSHP installs cost significantly more to install but receive the same grant amount.
- EPC requirement: A valid Energy Performance Certificate with no outstanding loft or cavity wall insulation recommendations, unless your installer confirms these aren't cost-effective for your property.
- Installer requirement: Must be fitted by an installer certified under the Microgeneration Certification Scheme (MCS) — the grant is claimed by the installer on your behalf and deducted directly from your quote, not paid to you as a reimbursement.
- Biomass note: Biomass boiler support under BUS was withdrawn from the scheme in April 2025 — only ASHP and GSHP installations currently qualify.
Typical Cost After the Grant
System Type | Typical Installed Cost | BUS Grant | Net Cost to Homeowner |
|---|---|---|---|
Air Source Heat Pump | £11,000–£16,000 | £7,500 | £3,500–£8,500 |
Ground Source Heat Pump | £20,000–£35,000 | £7,500 | £12,500–£27,500 |
Current Waiting Times: What's Driving the Backlog
Demand for MCS-certified installers has risen sharply through 2025–2026, driven by rising gas prices and expanded local authority retrofit schemes running alongside BUS. Homeowners should expect:
- Initial survey booking: 2–4 weeks from first enquiry with a reputable installer
- Quote-to-installation slot: 6–12 weeks in most regions, longer in high-demand areas like the South East and parts of Scotland's equivalent Home Energy Scotland scheme
- Total time from enquiry to a working heat pump: typically 8–16 weeks end to end
How to Shorten the Wait
- Get 3 MCS installer quotes in parallel rather than sequentially — this is the single biggest lever homeowners have over total wait time.
- Apply in late summer or early autumn (like now, August 2026) to avoid the pre-winter surge in October–December, when installer books fill fastest.
- Confirm grant fund availability with your installer upfront — BUS operates on a first-come basis and Ofgem periodically reports funding drawdown levels.