A Homeowner's Guide to the Boiler Upgrade Scheme

The Boiler Upgrade Scheme (BUS) is a UK government programme designed to help homeowners in England and Wales afford the cost of switching to a low-carbon heating system. Administered by the energy regulator Ofgem, the scheme offers upfront grants to reduce the purchase and installation cost of technologies like heat pumps and, in some cases, biomass boilers. By replacing an old fossil fuel system - such as a gas or oil boiler - you can make your home greener and more energy-efficient.

This initiative is a key part of the government’s strategy to meet its net-zero emissions target by 2050. The scheme is installer-led, meaning your chosen certified installer will apply for the grant on your behalf and deduct it directly from your final bill. The Boiler Upgrade Scheme is scheduled to run until at least 2028, providing a significant window for homeowners to take advantage of the funding.

Are You Eligible for the Grant?

To qualify for a grant through the Boiler Upgrade Scheme, both you and your property must meet several specific criteria. The scheme is aimed at existing homes and is not generally available for new-build properties, although some self-build projects may be eligible.

• Property Location: Your property must be located in England or Wales. Scotland and Northern Ireland have their own separate support schemes.

• Ownership: You must be the owner of the property. This includes your primary residence, second homes, and properties you rent out to tenants.

• Heating System: The grant must be for replacing an existing fossil fuel heating system (like gas, oil, or LPG) or a direct electric system (such as storage heaters). Low-carbon heating systems are not eligible for replacement under the scheme.

• Energy Performance Certificate (EPC): Your property must have a valid Energy Performance Certificate (EPC) issued in the last 10 years. Crucially, the EPC must not have any outstanding recommendations for loft or cavity wall insulation. If it does, you’ll need to carry out this work and get a new EPC before you can apply.

• System Capacity: The new heating system's output must not exceed 45kW thermal (written 45kWth in the scheme rules). This covers the vast majority of domestic properties.

What Heating Systems Are Covered?

The scheme provides grants for three main types of low-carbon heating technology. Your choice will depend on your property type, location, and budget.

• Air Source Heat Pumps (ASHPs): These systems absorb heat from the outside air and use it to warm your home’s heating and hot water systems. This category includes both air-to-water and, since April 2026, air-to-air heat pumps.

• Ground Source Heat Pumps (GSHPs): These draw heat from underground via a network of pipes. They are typically more expensive to install but can be more efficient than air source models. This category also covers water source heat pumps, which extract heat from a nearby body of water.

• Biomass Boilers: These burn organic matter, such as wood pellets or logs, to generate heat. Eligibility for a biomass boiler grant is restricted to properties in rural locations that are not connected to the gas grid.

How Much Funding Can You Get?

The grant is a fixed, one-off payment that contributes towards the total cost of the system and its installation. The amount varies depending on the technology you choose. Your installer will deduct the grant value from your quote, so you pay the lower price upfront.

Additionally, a temporary grant uplift is available for certain properties. Homes that are not connected to the gas grid - for example, those heated by oil or LPG - can receive a grant of £9,000 for an air or ground source heat pump. This increased funding is available for installations commissioned between 21 July 2026 and 31 March 2027.

How to Apply for the Boiler Upgrade Scheme

The application process is managed by your installer, which simplifies the journey for the homeowner. Here are the key steps involved:

1. Find a certified installer. You must use an installer certified by the Microgeneration Certification Scheme (MCS) to be eligible for the grant. It’s always wise to get quotes from at least three different companies to compare costs and approaches.

2. Confirm your eligibility. The installer will visit your property to assess its suitability and confirm that you and your proposed installation meet all the scheme’s requirements.

3. Agree on a quote. Once you’ve chosen an installer, they will provide a final quote that clearly shows the BUS grant deducted from the total cost.

4. The installer applies for the grant. Your installer will submit the grant application to Ofgem on your behalf.

5. Provide your consent. Ofgem will contact you directly by email to confirm that you have agreed for the installer to act on your behalf. You must provide this consent for the application to proceed.

6. Complete the installation. The MCS-certified installer will fit and commission your new low-carbon heating system according to the required standards.

7. The installer redeems the voucher. After commissioning the system, the installer redeems the grant voucher from Ofgem. You are only responsible for paying the difference as shown on your quote.

Finding a Certified Installer

Choosing the right installer is the most important step in the process. Only installations carried out by an MCS-certified professional are eligible for the Boiler Upgrade Scheme. MCS is a standards organisation that provides assurance for both the quality of the technology and the competence of the installer.

When researching installers, you should also check that they are a member of a consumer code body, such as the Renewable Energy Consumer Code (RECC) or the Home Insulation and Energy Systems Quality Assured Contractors Scheme (HIES). This provides extra protection and a clear process for resolving any disputes.

Frequently Asked Questions

Can I Apply for the Grant Myself?

No, you cannot apply directly. The Boiler Upgrade Scheme is an installer-led programme, meaning your chosen MCS-certified installer is responsible for submitting the grant application to Ofgem on your behalf.

How Long Is the Grant Voucher Valid For?

Once Ofgem issues a grant voucher, it has a limited validity period. For air source heat pumps and biomass boilers, the voucher is valid for three months. For ground source heat pumps, which often require more complex groundwork, the validity period is extended to six months.

Does the Grant Cover the Full Cost of Installation?

No, the grant is a contribution towards the total cost, not a full payment. The homeowner must cover the remaining balance. Typical installation costs can be around £11,500 for an air source heat pump and between £15,000 - £20,000 for a ground source heat pump, so the grant provides a significant discount but does not eliminate the upfront investment.

Can I Get the Grant for a New-Build Property?

In most cases, no. The scheme is designed to encourage the replacement of fossil fuel systems in existing properties. Standard new-build homes are not eligible. The only exception is for self-build properties, which may qualify if the owner can provide sufficient evidence that it is a genuine self-build project.

Can I Still Get the Grant if I Receive Other Energy Efficiency Funding?

Yes, you can. The Boiler Upgrade Scheme grant can be used alongside other funding for separate energy efficiency measures. For example, if you receive a grant for new windows, doors, or insulation, you are still eligible to apply for the BUS to help fund your new heating system.

Is the Boiler Upgrade Scheme Right for You?

The Boiler Upgrade Scheme offers a substantial financial incentive for homeowners in England and Wales to transition away from fossil fuels. By providing thousands of pounds towards the cost of a heat pump or biomass boiler, it makes these highly efficient, environmentally friendly systems more accessible than ever before. Whilst a significant personal investment is still required, the scheme is a crucial step in helping you reduce your home’s carbon footprint and future-proof it against rising energy costs.