What is the Boiler Upgrade Scheme?

The Boiler Upgrade Scheme (BUS) is a UK government grant that helps homeowners in England and Wales replace fossil fuel heating systems with low-carbon alternatives. It provides £7,500 towards an air source heat pump, £7,500 towards a ground source heat pump, and £5,000 towards a biomass boiler. The grant is applied directly by the installer, reducing the upfront cost.

Who is eligible for the Boiler Upgrade Scheme?

You are eligible if you own the property (including landlords), the property is in England or Wales, it has a valid EPC with no outstanding loft or cavity wall insulation recommendations (or you have addressed them), and you are replacing an existing fossil fuel heating system such as gas, oil, or LPG. New builds, social housing, and properties that already have a heat pump are generally excluded.

How do I apply for the Boiler Upgrade Scheme?

You do not apply directly. You choose an MCS-certified installer, get a quote, and the installer applies for the BUS voucher on your behalf through Ofgem. Once approved (usually within a few weeks), the grant amount is deducted from your installation cost. You pay the installer the remaining balance.

Can I get the Boiler Upgrade Scheme for a gas boiler replacement?

No. The scheme only covers the installation of air source heat pumps, ground source heat pumps, or biomass boilers. It does not fund replacing a gas boiler with another gas boiler. The aim is to move homes away from fossil fuel heating.

Boiler Upgrade Scheme Explained — Grants for Heat Pumps and Biomass | PocketWise

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.

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

Related guides: