What’s the difference between the BUS grant, ECO4, and the Warm Homes Plan?

The Honest Answer: What’s the difference between the BUS grant, ECO4, and the Warm Homes Plan?

They’re three separate schemes, each with:

• Different eligibility
• Different amounts
• Different purposes

The confusion between these three is one of the most consistent and costly mistakes I encounter across Hampshire. It regularly stops eligible homeowners from applying for funding they are fully entitled to.

Here is the plain English version, the explanation I give at every survey where a customer has already ruled themselves out of something they qualify for.

What is the Boiler Upgrade Scheme?

The Boiler Upgrade Scheme, the BUS grant, is the scheme AES works with. It provides £7,500 toward the cost of replacing a fossil fuel boiler or direct electric heating with a heat pump.

There is no income requirement. No means test. No benefits check. Any homeowner, landlord, or self-builder who has an eligible property with a valid EPC and an existing fossil fuel or direct electric heating system can apply. The heat pump must fully replace the fossil fuel system. A hybrid or bivalent arrangement does not qualify.

The grant is deducted from your invoice by the installer. AES applies to Ofgem for payment after the installation is complete. You never pay the full amount upfront.

What is ECO4?

ECO4 is a completely different scheme. It is targeted at low-income households and people in social housing. It funds a wider range of energy efficiency improvements, insulation, heating upgrades, and sometimes heat pumps, but it is means-tested and delivered through a different route.

AES does not operate under ECO4. If you are on certain qualifying benefits, live in social housing, or have a low household income, ECO4 may be available to you, but you would need to contact your energy supplier or local authority, not a company like AES.

The reason the confusion between BUS and ECO4 matters: many homeowners assume the heat pump grant is means-tested because they have heard of ECO4. It is not. They are two completely separate programmes.

What is the Warm Homes Plan?

The Warm Homes Plan is the government’s upcoming scheme that will replace ECO4. It is expected to be similarly targeted at lower-income households, with a broader scope of home improvements covered. As of April 2026, the full details of the Warm Homes Plan have not yet been confirmed.

AES will not operate under the Warm Homes Plan, just as we do not operate under ECO4. Our focus is on the BUS grant, the scheme available to the majority of Hampshire homeowners replacing a fossil fuel boiler with a heat pump.

Which scheme applies to you?

The question is straightforward. If you own a property, or rent one out, and it currently has a gas boiler, oil boiler, LPG system, or direct electric heating, and you want to replace that system with a heat pump, the BUS grant is the relevant scheme. Income level does not affect your eligibility.

If you are on qualifying benefits or have a low household income and want a broader package of home improvements including insulation, ECO4 or the Warm Homes Plan may be relevant. For that route, contact your energy supplier directly.

At AES, we check BUS eligibility at every free survey. If you qualify, and most Hampshire homeowners with a fossil fuel boiler do, we confirm it in writing and handle the full application on your behalf.

Related reading:

What is the Boiler Upgrade Scheme and who is it actually for ?
Does the £7,500 BUS grant cover the full cost of a heat pump ?

If the confusion between these schemes has been stopping you from enquiring, book a free survey. We will confirm which scheme applies to your property and give you the full picture in writing.

Call AES Limited on 01794 830 404 or contact us to book your free survey.