Boiler Replacement Grants in the UK: Complete 2026 Guide

Introduction#

Replacing an old boiler with a new, energy-efficient model can significantly reduce energy bills and carbon emissions, but the upfront cost puts many households off. Fortunately, as detailed in our complete guide to government energy grants, UK homeowners have access to several government-backed grants that can cover part or all of the cost. This guide brings together everything you need to know about boiler replacement grants in 2026: which schemes are available, who qualifies, and exactly how to apply. For a complete overview of all boiler options, see our comprehensive boilers guide.

Available Grant Schemes for 2026#

ECO4 (Energy Company Obligation)#

The ECO4 scheme is the largest government initiative supporting free or subsidised boiler replacements. It mandates large energy suppliers to fund energy-saving measures -- including boiler replacements -- for eligible households. The scheme primarily targets low-income households and those most vulnerable to fuel poverty.

• What it covers: Full cost of a new boiler, plus other energy efficiency measures such as insulation.
• Who funds it: Major energy suppliers (British Gas, EDF, E.ON, etc.).
• Eligibility: Primarily for households on low incomes or receiving means-tested benefits (see eligibility section below).
• Duration: The scheme runs until 2026, with the government expected to announce successor arrangements.

For more detail on the ECO4 scheme specifically, see our guide on applying for ECO4 grants.

Boiler Upgrade Scheme (BUS)#

The Boiler Upgrade Scheme offers grants to homeowners replacing fossil fuel heating with low-carbon alternatives such as heat pumps. As of 2026, the scheme has expanded eligibility to include additional household types.

• Grant amounts: Up to £7,500 towards air source heat pump installations; up to £5,000 for ground source heat pumps.
• Who qualifies: Most UK homeowners in England and Wales with an existing fossil fuel heating system.
• Key requirement: The property must have a valid Energy Performance Certificate (EPC) and adequate insulation.

Learn more in our guide on qualifying for the Boiler Upgrade Scheme.

Great British Insulation Scheme (GBIS)#

While primarily focused on insulation, GBIS can sometimes fund heating improvements as part of a broader package of energy efficiency measures for eligible households. Learn more in our guide to the Great British Insulation Scheme.

Local Authority Grants#

Many local councils in the UK offer additional funding for boiler replacements, tailored to specific regional needs. These schemes vary by area and often have their own eligibility criteria and application processes.

• How to find them: Contact your local council's housing or energy team, or search the Simple Energy Advice website.
• Typical support: Ranges from small contributions to full funding, depending on the area and your circumstances.

Eligibility Criteria#

Eligibility for boiler replacement grants generally depends on several factors. Each scheme has its own specific requirements, but common criteria include:

Income and Benefits#

Most grant schemes target low-income households. You are likely eligible if you receive any of the following:

• Universal Credit
• Pension Credit (Guarantee Credit)
• Child Tax Credit (with income below the threshold)
• Working Tax Credit
• Income Support
• Income-based Jobseeker's Allowance (JSA)
• Income-related Employment and Support Allowance (ESA)
• Housing Benefit

Property Type#

• Owner-occupied homes generally have priority under ECO4.
• Private tenants may qualify with landlord permission.
• Social housing tenants should contact their housing association, who may apply on their behalf.

Current Boiler Condition#

Your existing boiler's efficiency is a key factor. Older boilers rated below 86% efficiency (typically those installed before 2005) are more likely to qualify for replacement. Boilers that are beyond economic repair also qualify.

EPC Rating#

Some schemes, particularly the Boiler Upgrade Scheme, require your property to have a valid EPC. Properties with lower energy efficiency ratings (D--G) are more likely to qualify for support.

For detailed eligibility checks, see our boiler grant eligibility guide or use the checker below.

Step-by-Step Application Process#

Step 1: Check Your Eligibility#

Use online eligibility checkers provided by energy companies, the Energy Saving Trust, or our grant checker below. You can also check your eligibility for the ECO4 scheme specifically.

Step 2: Gather Your Documents#

Prepare the following before applying:

• Proof of income or benefits (e.g., Universal Credit statement, pension credit award letter)
• Proof of home ownership or tenancy agreement
• Details of your current boiler (make, model, age if known)
• A recent energy bill
• Your property's EPC certificate (if available)

Step 3: Contact an Approved Installer or Energy Supplier#

For ECO4, reach out to your energy supplier or an approved installer who partners with energy companies. For the Boiler Upgrade Scheme, you will need an MCS-certified installer.

Step 4: Home Assessment#

A professional will visit your home to assess the suitability of a new boiler installation. They will check your current heating system, insulation levels, and overall energy efficiency.

Step 5: Approval and Installation#

Once approved, the installation will be scheduled. Under ECO4, the work is typically carried out at no cost to the homeowner. Under the Boiler Upgrade Scheme, the grant is applied as a discount at the point of installation.

Step 6: Follow Up#

After installation, you should receive documentation confirming the work done, the new boiler's warranty details, and updated energy efficiency information. Keep these records safe.

Benefits of Upgrading Your Boiler#

Cost Savings#

Modern A-rated condensing boilers are significantly more efficient than older models. According to the Energy Saving Trust, replacing an old G-rated boiler with a new A-rated model could save you up to £300 per year on energy bills. Over the 15-year lifespan of a boiler, that adds up to thousands of pounds.

Environmental Impact#

New boilers emit less carbon dioxide per unit of heat produced. Upgrading is a meaningful step towards reducing your household's carbon footprint, supporting the UK's commitment to net-zero emissions by 2050.

Improved Comfort#

Enhanced efficiency means faster heating and more consistent temperatures throughout your home. Modern boilers also tend to be quieter and more compact than older models.

For more on choosing the right replacement model, see our guide to the best energy efficient boilers for 2026. If you are considering alternatives to a gas boiler, explore our guide to eco-friendly boilers and alternatives.

Frequently Asked Questions#

Practical Next Steps#

1. Check Your Eligibility: Use the grant checker below or consult the Energy Saving Trust.
2. Prepare Your Documentation: Gather all necessary paperwork to streamline your application.
3. Contact a Local Installer: Reach out to an approved installer or your energy supplier to begin the process. For options, explore our affordable boiler replacement options.
4. Consider Your Options: If your current boiler is beyond repair, weigh up whether a like-for-like replacement or a switch to a heat pump makes more sense for your home.

Sources#

• GOV.UK: Energy Company Obligation (ECO4) Scheme
• GOV.UK: Energy Grants Calculator
• Energy Saving Trust: Boiler Upgrade and Efficiency
• Ofgem