If you are planning insulation, heating upgrades, and grant-backed home improvements together, use the Energy Efficiency Hub as your main route map.
The Boiler Upgrade Scheme (BUS) provides government grants of up to £7,500 to help homeowners in England and Wales switch from gas, oil, or LPG boilers to low-carbon heating systems like heat pumps.
Read more: See our Energy Grants guide for a complete overview of this topic.
Grant Amounts
| Technology | Grant amount | Typical installed cost | You pay (approx.) |
|---|---|---|---|
| Air source heat pump | £7,500 | £10,000–£18,000 | £2,500–£10,500 |
| Ground source heat pump | £7,500 | £15,000–£35,000 | £7,500–£27,500 |
| Biomass boiler | £5,000 | £10,000–£20,000 | £5,000–£15,000 |
The grant is deducted from the installer’s quote — you never receive the money directly.
Eligibility
| Requirement | Details |
|---|---|
| Property location | England or Wales |
| Property ownership | You must own the property (homeowners and landlords) |
| Existing heating | Must be replacing a fossil fuel system (gas, oil, LPG, electric — not another heat pump) |
| EPC | Must have a valid EPC dated within the last 10 years |
| Insulation | EPC must not recommend loft or cavity wall insulation (or you must have completed these first) |
| Property type | Existing buildings only — new builds are excluded |
| Social housing | Excluded (has separate schemes) |
| Previous BUS grant | Only one grant per property |
Who Cannot Get a BUS Grant?
| Excluded | Reason |
|---|---|
| New build properties | Separate building regulations apply |
| Social housing | Covered by Social Housing Decarbonisation Fund |
| Properties already with a heat pump | System must replace fossil fuel heating |
| Properties with outstanding insulation recommendations on EPC | Must insulate first |
| Scotland and Northern Ireland | Have separate schemes |
The EPC Requirement
Your property needs a valid EPC. Crucially, the EPC must not recommend loft insulation or cavity wall insulation as improvements. If it does, you need to either:
| Situation | What to do |
|---|---|
| EPC recommends loft insulation | Install loft insulation (£300–£600), then get a new EPC |
| EPC recommends cavity wall insulation | Install cavity wall insulation (£500–£1,500), then get a new EPC |
| Solid wall property (no cavity) | This recommendation will not appear — no action needed |
| No valid EPC | Get one (£60–£120) |
This is the most common reason applications are rejected, so check your EPC at gov.uk/find-energy-certificate before proceeding.
How to Apply
You do not apply directly. The process works through your installer.
| Step | What happens |
|---|---|
| 1. Check eligibility | Confirm you meet the criteria above |
| 2. Get quotes | Contact MCS-certified installers (at least 3 is recommended) |
| 3. Choose an installer | Agree a quote — installer applies for voucher |
| 4. Voucher issued | Ofgem reviews and issues voucher (usually 2–4 weeks) |
| 5. Installation | Installer completes the work |
| 6. Payment | You pay the installer the total minus the grant — installer redeems voucher from Ofgem |
Finding MCS-Certified Installers
Only MCS-certified installers can apply for BUS vouchers. Search at mcscertified.com to find accredited installers in your area.
| Tip | Why it matters |
|---|---|
| Get at least 3 quotes | Prices vary significantly |
| Check MCS accreditation | Non-MCS installers cannot access the grant |
| Ask about the full process | Good installers handle the voucher application for you |
| Check installer reviews | MCS certification does not guarantee quality of work |
| Confirm what is included | Ensure quote covers radiator upgrades, hot water, controls |
What the Grant Covers
| Covered | Not covered |
|---|---|
| Supply and installation of heat pump or biomass boiler | Radiator upgrades (may be needed for heat pumps) |
| Commissioning and controls | Underfloor heating installation |
| Removal of old system | Electrical upgrades (may be needed) |
| Hot water cylinder (if part of system) | Insulation improvements |
Some installers include radiator upgrades and ancillary work within their quote, effectively using the grant to reduce the total package price.
Air Source Heat Pump — What to Expect
| Factor | Details |
|---|---|
| Running cost vs gas boiler | Roughly similar at current electricity/gas prices |
| Lifespan | 20–25 years |
| Maintenance | Annual service recommended (£100–£200) |
| Noise | Low hum from outdoor unit — comparable to a fridge |
| Space needed | Outdoor unit roughly 1m x 1m, plus indoor cylinder |
| Performance in cold weather | Modern units work efficiently down to –15°C or below |
| Radiators | May need upsizing as heat pumps run at lower flow temperatures |
| Hot water | Usually via a hot water cylinder (combi heat pumps are emerging) |
Running Cost Comparison
| Heating system | Fuel cost per kWh | Efficiency | Effective cost per kWh of heat |
|---|---|---|---|
| Gas boiler | 7p | 90% | 7.8p |
| Oil boiler | 6–8p | 85% | 7–9.4p |
| Air source heat pump | 24p electricity | 300% (COP 3.0) | 8p |
| Ground source heat pump | 24p electricity | 400% (COP 4.0) | 6p |
| Direct electric heating | 24p | 100% | 24p |
Heat pumps are most cost-effective when they achieve a high Coefficient of Performance (COP), which depends on the system design and property insulation.
BUS Budget and Availability
| Detail | Status |
|---|---|
| Scheme launch | April 2022 |
| Current end date | March 2028 (extended from original 2025 end date) |
| Budget | £1.5 billion over the scheme lifetime |
| Demand | Applications have increased significantly — vouchers are not guaranteed indefinitely |
Apply sooner rather than later if you are interested, as the scheme could be modified or budgets reallocated.
Alternatives If You Do Not Qualify
| Situation | Alternative |
|---|---|
| In Scotland | Home Energy Scotland grant and loan scheme |
| In Northern Ireland | Northern Ireland Sustainable Energy Programme (NISEP) |
| Social housing | Social Housing Decarbonisation Fund |
| New build | Developer should install compliant heating under building regs |
| Want to keep gas boiler | No BUS grant, but consider a hydrogen-ready boiler for future |
| Cannot afford remainder after grant | Some local authorities offer additional top-up grants |
Common Questions
| Question | Answer |
|---|---|
| Can I combine BUS with other grants? | Generally not with ECO4 or GBIS for the same measure, but check with your installer |
| Do I need planning permission for a heat pump? | Usually not — most are permitted development, but check if listed or in a conservation area |
| How long does installation take? | 2–5 days typically for an air source heat pump |
| Will I need a bigger electricity supply? | Most homes do not, but your installer will check |
| Can I get a grant for a hybrid heat pump? | Not through BUS — hybrids combine a heat pump with a gas boiler and are not eligible |
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