Commercial solar grants and funding in the UK for 2026 — the honest picture

Let's start with the thing most articles bury: there is no general cash grant for an ordinary SME putting solar on its roof in 2026. If you run a warehouse, an office, or a shop and you're hoping the government will write off a chunk of the install, the honest answer is that it won't — not directly.

That sounds like bad news. It mostly isn't, because the support that does exist comes through the tax system and is often worth more than a grant would be. The trouble is that it's less visible, so businesses either miss it or get told about it by an installer with an incentive to make the numbers look good. Here's the real picture.

What's actually available

There are four routes worth knowing about. Only one or two will apply to you.

Capital allowances (applies to almost everyone). This is the big one, and we cover it in detail below. In short: you can deduct the full cost of a solar installation from your taxable profits, usually in the first year.

The Local Growth Fund (regional, limited). The UK Shared Prosperity Fund — for years the most common route to a small commercial solar grant — closed to new applications on 31 March 2026. Its successor, the Local Growth Fund, launched on 1 April 2026 but covers only 11 Mayoral Strategic Authority areas. If you're in one of those regions, it's worth checking with your combined authority, but don't build your business case around it.

Salix Finance (public sector only). Salix offers interest-free loans for energy efficiency and renewable projects — but only to public sector bodies (schools, NHS trusts, councils). If you're a private business, this isn't for you. If you're a multi-academy trust or similar, it's genuinely useful.

The Industrial Energy Transformation Fund (large industrial only). The IETF, run by the Department for Energy Security and Net Zero, offers direct grants — up to £30 million — for industrial decarbonisation, and solar PV is explicitly eligible. But this is aimed at energy-intensive manufacturing, not a 60-panel install on a distribution unit. If your annual energy spend runs into the hundreds of thousands, look at it. Otherwise, skip it.

For the typical SME, that leaves capital allowances doing the heavy lifting. So let's be precise about how they work, because this is where installers' "you'll save 50% in tax" claims tend to fall apart under scrutiny.

The real lever: capital allowances

Solar panels are classified as special rate plant and machinery for capital allowances. That classification matters, because it changes which reliefs apply.

Here's what you can claim in 2026:

• The Annual Investment Allowance (AIA) gives you a 100% first-year deduction on the first £1 million of qualifying capital expenditure each year. Solar qualifies. For any SME installation — which will be well under £1 million — this means you deduct the entire cost of the system from your taxable profits in the year you install it.
• Above £1 million, the 50% First-Year Allowance applies to the special-rate portion: you deduct half in year one, and the remainder enters the special-rate pool, written down at 6% a year on a reducing balance.

One important correction to a claim you'll sometimes hear: solar does not qualify for the headline "full expensing" 100% relief that applies to main-rate plant. That's a separate scheme for a different asset class. For solar, AIA is your 100% route — and for any normal SME spend, AIA covers the whole thing anyway, so the distinction rarely costs you anything.

What the tax relief is actually worth

This is where honesty matters. A 100% deduction is not the same as getting the money back.

Say you install a system for £100,000. With AIA, you deduct £100,000 from your taxable profits. At the 2026 main corporation tax rate of 25%, that deduction saves you £25,000 in corporation tax — so your effective net cost is around £75,000.

If your profits sit in the £50,000–£250,000 band, your marginal rate is slightly higher (26.5%), so the saving is a touch more. But the figure to hold in your head is "roughly a quarter of the cost back in tax," not "half." When an installer's proposal implies a 40–50% reduction, they're usually stacking the VAT reclaim on top — which is real, but only if you're VAT-registered (see below), and it's a separate mechanism.

VAT: the residential 0% rate does not apply to you

You may have read that solar is "0% VAT." That's true — for homes. The zero rate on residential solar runs to 31 March 2027. It does not extend to standard commercial premises, which pay the full 20% VAT on a solar installation.

The saving grace: if your business is VAT-registered (most are), you reclaim that 20% through your normal VAT return, the same as any other business purchase. So the 20% isn't a true cost — it's a cash-flow timing issue. If you're not VAT-registered, the 20% is a genuine cost you can't recover, and you should factor the gross price into your payback maths.

Business rates: a quiet 10-year exemption

Here's a relief almost nobody mentions: solar panels installed on business premises are exempt from business rates as plant and machinery, and that exemption is legislated to run until April 2035. Adding solar won't increase your rateable value. It's not a headline saving, but it removes a cost you might otherwise have feared.

The Smart Export Guarantee: ongoing income, not a grant

Once your system is running, the electricity you don't use on-site is exported to the grid, and the Smart Export Guarantee (SEG) pays you for it.

In 2026, business SEG tariffs range from around 8.5p/kWh to 15p/kWh depending on supplier and tariff type — British Gas, EDF and others have been at the top of the table, while some suppliers sit lower. Fixed tariffs give you certainty; variable tariffs track the wholesale power curve, paying more when wholesale prices are high.

Two things to know:

1. SEG income is taxable. HMRC treats it as trading income, subject to corporation or income tax.
2. You have to choose your SEG supplier — it doesn't have to be your electricity supplier, and the rate you're offered varies a lot, so it's worth shopping around. Eligibility requires an MCS-certified install, a smart meter capable of half-hourly readings, and that you're not still on the old Feed-in Tariff.

For most commercial systems, export is 20–30% of the total financial benefit — useful, but the bigger value is always in the electricity you use yourself, because that offsets your full retail rate (around 28p/kWh) rather than the lower export rate.

How to pay for it: cash, asset finance, or a PPA

Three broad routes, briefly:

• Cash purchase — best returns, you own the asset and capture all the allowances and savings. Right if you have the capital and want the fastest payback.
• Asset finance / leasing — you spread the cost, preserve working capital, and often still claim allowances (depending on the structure — check with your accountant). The finance cost eats into returns but the project can be cash-flow positive from day one.
• Power Purchase Agreement (PPA) — a third party funds and owns the system on your roof, and you buy the electricity it generates at an agreed rate, usually below grid price. Zero upfront cost, but you don't own the asset or get the allowances, and you're tied into a long contract. Most common where the business can't or won't use capital, or on a leased building.

Sanity-checking the financial claims in a quote

When an installer's proposal lands, four checks:

1. The tax claim. If it says "100% tax relief," that's AIA — correct in substance, but make sure they're describing a deduction (worth ~25% of cost in cash tax), not implying you get the full amount back.
2. The VAT line. For a commercial quote it should show 20% VAT. If you're VAT-registered, note it's reclaimable; if it's quoted at 0%, that's a residential template and the number is wrong for you.
3. The SEG rate. A figure of 5–8p is conservative; 10–15p is achievable on the best fixed tariffs but assumes you switch and lock in. Anything above 15p is optimistic for 2026.
4. The grant. If a quote leans on a "government grant" to make the payback work, ask exactly which scheme — and check it against the four above. For an ordinary SME, the honest answer is usually that no cash grant applies, and a proposal that depends on one is a proposal to be wary of.

The bottom line

The 2026 support for commercial solar isn't a cheque in the post — it's a stack of tax reliefs: 100% capital allowances (worth about a quarter of the cost back), reclaimable VAT if you're registered, a business-rates exemption to 2035, and ongoing SEG income on what you export. Add those to the electricity you stop buying, and the case stands up on its own without a grant.

To see what the numbers look like for your building, run the calculator. For the detail on payback periods and the assumptions that drive them, read our guide on commercial solar payback in 2026. And for a monthly read on where rates, tariffs and rules are heading, subscribe to the Brief — independent, and written for buyers rather than installers.

This guide is general information, not tax advice. Confirm the treatment for your specific business with your accountant before committing.