Should I move from sole trader to a limited company?

It depends on profit level, whether you need to retain cash in the business to fund stock and vans, and how you are paid by the contractors you work for. It is not automatically better, and the switch carries its own costs. We will tell you what each option leaves you with on your actual numbers rather than a general rule.

We install on our own premises. Can we claim the panels?

Yes, but not under full expensing. Solar panels are designated special rate expenditure, so a company claims either the Annual Investment Allowance, which does reach special rate spend and covers up to £1 million, or the 50% first-year allowance. Which is better depends on how much other capital spend the year already carries.

Do you handle payroll for fitters on day rates?

Yes, and the first question is usually whether they are employees or genuinely self-employed, because the answer drives both payroll and CIS. We look at how the work is actually arranged rather than what the paperwork says, since that is the test HMRC applies.

Solar trade guidance

Accountants for Solar Installation Companies

Written and reviewed by the Solar Installer Accountants editorial team. Last reviewed 22 August 2026.

Technician inspecting a large commercial rooftop photovoltaic array

We act for limited companies installing solar: the annual accounts, the corporation tax return, payroll for your fitters, and the CIS obligations that arrive the moment you subcontract or are subcontracted to. Directors' own returns are handled alongside so nothing falls between the company and the person.

Everything is a fixed fee, agreed in writing before any work starts, and it covers the questions through the year rather than metering them.

What We Handle

Statutory accounts and the corporation tax return, the confirmation statement, payroll and pension enrolment for your fitting teams, and VAT returns. Where you engage subcontract labour we run the CIS side: verification, the deduction at the right rate, and the monthly return with its own deadline and its own penalties.

On the capital side, a solar company is the case where the allowance you pick matters most. Full expensing does not reach solar panels, so a company buying an array, whether for a demonstration site or its own premises, needs the claim routed correctly or it loses relief in the year it can least afford to.

Where a Solar Company's Position Gets Awkward

Mixed work is the usual difficulty. A company doing domestic roofs and commercial rooftops in the same quarter is running zero-rated and standard-rated sales side by side, sometimes on the same customer. The return has to reflect that split accurately, and the underlying quotes have to have been priced on the right assumption in the first place.

The second is being a contractor and a subcontractor at once, which is common as a solar firm grows. You are deducting CIS from the fitters you pay and having it deducted by the main contractor you invoice, with the reverse charge sitting on top wherever the supply is standard or reduced rated. Each of those has its own filing and its own timing.

How It Runs

We agree what the company needs at the start: year end only, or year end plus payroll, VAT and CIS through the year. Most solar companies take the second, because the monthly obligations are the ones that carry penalties.

You keep your bookkeeping where it already works and we connect to it. If it does not work we will say so and fix it once, rather than moving you onto something new every year.

What It Costs

A fixed fee, quoted before we begin. It scales with what is actually running: number of people on payroll, whether CIS applies, VAT frequency, and how much of the bookkeeping you want to keep in house.

To get a price, tell us about your solar work and we will come back with a fixed quote and a deadline.