Government solar loans are coming.
Here's what we actually know.

The Warm Homes Loan Scheme promises cheap or free finance for solar panels, batteries, and heat pumps. Some of the details are solid. Others are still missing.

What is the Warm Homes Loan Scheme?

It is part of the government's wider Warm Homes Plan, a £15 billion programme to upgrade five million homes by 2030. The loan scheme sits alongside the existing Boiler Upgrade Scheme grant and the Warm Homes: Local Grant for lower-income households.

The basic idea: the Treasury pays participating lenders a capital grant worth up to 20% of each loan they issue. In return, the lender must pass that saving on as a lower interest rate. The government says this could cut rates by up to five percentage points. So a lender that would normally charge 9% might offer 4%. Some deals could reach 0%, though that is not guaranteed.

Loans must run for a minimum of three years. Beyond that, terms are up to the lender.

What can you borrow?

The scheme covers most home energy technologies. Each has its own loan cap:

Heat pump loans can also cover the cost of new radiators and pipework. An EV charger can be included when bundled with a solar or battery installation.

Who is eligible?

The scheme is open to owner-occupiers and private landlords across the UK — England, Scotland, Wales, and Northern Ireland.

There is no income threshold and no minimum EPC rating. You do not need to be on benefits or in fuel poverty. This is a universal scheme.

That said, lenders will still run their own credit and affordability checks. The government is not lending the money directly. You borrow from a bank or finance provider, and they decide whether to approve you based on your income, credit history, and the usual criteria. The subsidy makes the rate cheaper, not the approval easier.

Businesses and company landlords are excluded in this first phase.

One important requirement: the installation must be carried out by an MCS-certified installer using MCS-certified products. This is the same standard required for the Boiler Upgrade Scheme and the Smart Export Guarantee.

Can you combine it with the Boiler Upgrade Scheme?

Yes. This is one of the most useful parts of the scheme.

The Boiler Upgrade Scheme currently offers £7,500 towards an air source or ground source heat pump, or £9,000 if you are replacing oil or LPG heating in an off-gas-grid home (the higher rate runs until 31 March 2027). Air-to-air heat pumps get £2,500, and biomass boilers get £5,000.

Your installer applies for the BUS grant and deducts it from the quote first. You then borrow only the remaining balance through the loan scheme. For a typical air source heat pump installation costing £10,000 to £14,000, the grant could leave you borrowing just a few thousand pounds — well within the £20,000 cap and potentially at a very low rate.

How much could you actually save?

Without confirmed rates, the exact numbers are illustrative. But here is the shape of it.

Say you borrow £10,000 over five years. At a standard personal loan rate of around 9%, you would pay roughly £2,700 in interest. If the scheme cuts that to 4%, total interest drops to about £1,300. That is a saving of around £1,400 over the life of the loan.

At 0%, you would repay exactly what you borrowed and nothing more.

For context, the cheapest mainstream personal loans currently sit around 5.9% APR for borrowing £7,500 or more. The scheme loans could beat that — but until lenders publish their products, we cannot say by how much.

What is NOT confirmed yet

This matters. The scheme has been announced, the rules have been published, and lender applications have opened. But several critical pieces are still missing:

Which lenders are participating. No bank or finance provider has been named. The first lender application window opened in June 2026 and closed in July. A second window is expected later, with lenders joining in early 2027.

The actual interest rates. "Up to five percentage points off" is a target, not a guarantee. Each lender will set its own rate based on its costs, your creditworthiness, and the loan size.

When you can apply. There is no consumer application route yet. The scheme was originally expected to open to borrowers in September 2026, but that date passed without a launch.

How you apply. Likely through a participating lender directly, through an approved installer working with a lender, or through a mortgage provider offering a qualifying green finance product. But none of this is confirmed.

The scheme runs until 31 March 2030, so there is time. But if you are waiting for this specific financing before going ahead with solar or a heat pump, you are waiting for an unknown date.

Watch out for scams

Any time the government announces free or cheap money, scammers follow. Be cautious of:

Unsolicited contact — texts, emails, or calls offering Warm Homes Plan loans. The scheme has no application process yet, so anyone offering one is lying.

Data-harvesting sites — websites collecting your personal details for a scheme that does not yet exist in consumer form.

Fake lenders — anyone claiming to be an approved lender or broker before lenders have been officially announced.

Lead-generation sites — dressed up as official government portals but designed to sell your details to installers.

When the scheme opens, applications will go through FCA-authorised lenders. If someone asks for your bank details or a deposit to "reserve your place," it is a scam.

What should you do now?

If you are considering solar panels, a battery, or a heat pump, the loan scheme does not change the underlying maths. The savings from generating your own electricity or switching off gas are the same whether you pay cash, borrow at 5%, or borrow at 0%. Cheaper finance just affects how quickly the investment pays for itself.

Here is what is worth doing today:

Get a proper quote. You will need an itemised quote from an MCS-certified installer to apply for any loan under this scheme. Getting one now means you are ready when lending opens. It also tells you whether the project makes financial sense at all.

Run the numbers. Use our solar panel calculator or heat pump calculator to see what your actual savings look like based on your roof, your usage, and current energy prices. The loan makes the upfront cost easier to manage — but only if the system pays back over its lifetime.

Check the Boiler Upgrade Scheme. If you are looking at a heat pump, the £7,500 grant (or £9,000 for oil/LPG replacements until March 2027) is available right now, with no waiting. You do not need to wait for the loan scheme to use it.

Do not overpay for urgency. Some installers may use the loan scheme announcement to push you into signing quickly. The scheme runs until 2030. Take your time, compare quotes, and make sure the system is right for your home.

Remember 0% VAT. Solar panels and batteries are currently at 0% VAT in Great Britain, but that ends on 31 March 2027. On a typical installation, that saves you £900 to £1,000. This deadline is more pressing than the loan scheme.

Updated October 2026. Sources: DESNZ, HM Treasury scheme rules (September 2026), Energy Saving Trust. Knowwatt is independent and does not arrange finance. Estimates only. Not financial advice.