Is solar a tax-deductible business expense?

Finance directors ask us this constantly: can the business simply write off the cost of a solar installation against profit, the way it would an electricity bill or a repair? The short answer is that solar PV is almost never a straightforward deductible expense. It is capital expenditure, and the relief comes through the capital allowances regime instead. That distinction sounds like accountancy hair-splitting, but it changes when you get the tax benefit, how much you get, and — crucially — whether your business or somebody else ends up claiming it.

This guide explains the rule, why it works the way it does, and how each finance route changes who gets the relief.

Revenue expense vs capital expenditure

A revenue expense is the cost of running the business day to day: stock, wages, energy, insurance, repairs. These are deducted in full against taxable profit in the year you incur them.

A solar array is different. It is an asset with an enduring benefit — it will generate electricity for 25 years or more. HMRC treats that as capital expenditure, so you cannot just subtract the invoice from your profit. Instead you claim capital allowances, which spread or accelerate the tax relief on the asset’s cost. So the honest answer to “can I claim solar panels as a business expense” is: not as a simple expense, but yes, the cost is relievable — usually on better terms than a plain deduction would give you.

The one genuine exception is maintenance. Cleaning, inverter servicing and repairs to keep an existing system working are revenue costs and are deductible in the normal way. The panels, mounting, inverters and associated wiring are the capital element.

How capital allowances deliver the relief

Solar PV is classified as special-rate (integral-feature) expenditure. That classification matters because it determines which allowances apply.

• Annual Investment Allowance (AIA) gives you 100% relief on up to £1m of qualifying spend per year. For most commercial installations the entire cost falls inside this cap, so you effectively deduct the whole lot in year one.
• Above £1m, the 50% first-year allowance (FYA) lets you write off half the excess immediately, with the balance entering the special-rate pool at 6% a year on a reducing basis.

Both AIA and the 50% FYA are permanent features of the regime, so you can plan around them with confidence.

One common misconception is worth correcting. Solar does not qualify for 100% full expensing — that uplift is reserved for main-rate plant and machinery. Because solar is special-rate, the AIA and the 50% FYA are the routes that apply. Our deeper companion on this sits at our capital allowances guide, which works through the numbers with a sector example.

The catch: you have to own the asset to claim

Here is the part that trips up most buyers. Capital allowances belong to whoever owns the asset. Your finance route decides ownership, and therefore decides who claims.

Hire purchase, equipment loan and cash purchase

Under hire purchase, an equipment loan or an outright cash purchase, your business owns the system (with HP, ownership transfers on the final payment, but you are treated as owner from the start for allowances). That means your business claims the AIA or 50% FYA in full, and your business keeps the Smart Export Guarantee (SEG) income from electricity you export. This is the structure that keeps every tax and revenue benefit inside your accounts — see how it works on solar hire purchase.

Finance lease

With a finance lease the lessor (the funder) usually claims the capital allowances, then passes the benefit back to you through lower rentals. You do not claim the allowances yourself, but your lease rentals are deductible as a business expense across the term. The exception is a long-funding lease, where the rules can shift the claim to the lessee. Detail on this route is on the solar finance lease page.

Operating lease

Under an operating lease you never become the owner, so there are no capital allowances for you. The trade-off is simplicity: the rentals are fully deductible as a revenue expense, and you hand the asset back at the end of the term. This can suit a business that cannot use allowances anyway — for example a loss-making or tax-exempt body.

Power Purchase Agreement (PPA)

A PPA is not finance at all — a third party owns the system on your roof and sells you the power. Because they own it, the funder claims the capital allowances and keeps the SEG export income. You pay only for electricity used, which is deductible, but you forfeit both the tax relief and the export revenue for the life of the contract. We compare the two head to head in asset finance vs PPA.

Why ownership usually wins on tax

Put the routes side by side and a pattern emerges. Owning the system via asset finance keeps the capital allowances and the SEG income inside your business. A PPA hands both to the funder in exchange for zero upfront capex. For a profit-making, tax-paying business, that combination of allowances plus export income is typically worth more than the convenience of a PPA — which is the core reason we lean towards ownership for most clients.

That said, the right answer depends on your tax position. A business with no taxable profit cannot use allowances, so the case for owning is weaker. This is where independent broking earns its keep: matching the structure to whether you can actually use the relief. Our solar grants for business guide covers how allowances, SEG and any regional support stack alongside the finance.

VAT and the 2026 accounting change

Two further points belong on a finance director’s checklist.

VAT. The VAT on commercial solar equipment is reclaimable by VAT-registered businesses. The timing differs by route: with HP or a loan you pay the VAT up front and reclaim it, whereas a lease spreads the VAT across the rentals. The domestic zero-rating you may have read about does not apply to commercial installations.

FRS 102. The revised FRS 102 brings most leases on-balance-sheet for lessees, for accounting periods beginning on or after 1 January 2026, with exemptions for short-term and low-value leases. If you have covenants tied to balance-sheet ratios, factor this in early — an operating lease that used to sit off-balance-sheet will, for many businesses, now appear as a right-of-use asset and a corresponding liability.

The practical takeaway

Solar is capital, not a simple expense, but the relief is real and often generous. The key decision is not whether you get tax relief — it is whether you get it or the funder does. Owning via hire purchase, an equipment loan or cash keeps the allowances and the export income with your business. A finance or operating lease still gives you deductible rentals, while a PPA hands the lot to the funder.

Tell us your tax position and roughly what you are spending, and we will model the after-tax cost of each route so you can see the difference in pounds. Request a no-obligation quote and we will set out which structure keeps the most value inside your business.