Sole trader or limited company? How an accountant helps you decide

"Should I be a sole trader or set up a limited company?" is one of the most common questions a new or growing UK business asks an accountant, and it does not have a single right answer that applies to everyone. What follows sets out the factual differences between the two structures — liability, tax treatment and administrative burden — without recommending one over the other, because the right choice genuinely depends on your own profit levels, plans and appetite for admin.

The most fundamental difference is legal liability. As a sole trader, you and your business are legally the same entity — there is no separation between your personal finances and your business finances in the eyes of the law. If the business runs up debts it cannot pay, or is sued, your personal assets are potentially at risk to satisfy those debts, not just whatever the business itself owns. A limited company, by contrast, is a separate legal entity from the people who own and run it. Shareholders' liability is generally limited to the amount they have invested in the company, and directors are not personally liable for the company's debts purely by virtue of being a director — though this protection is not absolute: directors can become personally liable in specific situations, such as giving a personal guarantee for a loan or lease, or being found to have continued trading while insolvent in a way that amounts to wrongful trading, and unpaid PAYE or National Insurance can sometimes be pursued personally from a director in certain circumstances.

Tax treatment is the second major difference, and it works on genuinely different systems. Sole traders pay Income Tax on their business profits through Self Assessment, using the same personal rates and bands that apply to any other income. For 2026/27, the personal allowance is £12,570, income between that and £50,270 is taxed at the basic rate of 20%, income between £50,270 and £125,140 is taxed at the higher rate of 40%, and income above £125,140 is taxed at the additional rate of 45% — with the personal allowance itself gradually withdrawn for income between £100,000 and £125,140. Sole traders also pay Class 4 National Insurance on their profits, on top of Income Tax — since compulsory Class 2 contributions were abolished for most self-employed people from April 2024, Class 4 is now the main additional charge, currently levied at 6% on profits between £12,570 and £50,270 and 2% above that; voluntary Class 2 remains available for those with profits below the small profits threshold who want to protect their State Pension record. NIC rates and thresholds change from year to year, so it is worth checking current HMRC rates rather than relying on a previous year's figures.

A limited company, by contrast, pays Corporation Tax on its profits rather than Income Tax. For 2026/27, companies with profits up to £50,000 pay the small profits rate of 19%, companies with profits above £250,000 pay the main rate of 25%, and profits falling between £50,000 and £250,000 attract marginal relief, which tapers the effective rate up smoothly across that band rather than jumping straight from 19% to 25% — these thresholds are also shared across any associated companies you control, which can push a company into a higher effective band sooner than expected if you run more than one. Once Corporation Tax has been paid, a director then typically extracts money from the company personally through a combination of salary, which is subject to Income Tax and National Insurance in largely the same way as any other employment income, and dividends, which are taxed under a separate set of dividend rates with their own tax-free allowance — figures that change fairly often, so it is worth checking current HMRC dividend rates rather than assuming a previous year's figures still apply. This two-stage structure — Corporation Tax on the company, then further tax on what is drawn out personally — is the main reason the "is a limited company more tax-efficient" question does not have a single fixed answer; it depends heavily on how much profit is involved and how much of it is actually withdrawn versus retained in the company.

Administrative burden is the third major difference, and it is often underweighted compared to the tax question. Sole traders have relatively light statutory obligations — registering with HMRC, keeping business records, and filing one Self Assessment return a year (or quarterly MTD updates instead, for those above the relevant income threshold), with no filings required at Companies House at all. A limited company involves meaningfully more: registering the company at Companies House, filing annual accounts prepared to the required format, filing a confirmation statement each year, submitting a separate CT600 Corporation Tax return, and maintaining statutory registers and records under the Companies Act. This additional administrative layer is a large part of why accountancy fees for a limited company typically run higher than for a sole trader with similar turnover.

None of this amounts to a recommendation of one structure over the other for your own situation — the right answer depends on your expected profit level, whether you plan to reinvest profits in the business, how much personal liability protection matters to you, and how much administrative complexity you are willing to take on. An accountant can model the actual numbers for your specific circumstances, which is generally more useful than a generic rule of thumb. This article is general information, not tax or accounting advice, and current tax rates and thresholds should always be checked against gov.uk or with a qualified accountant before you make a decision. Our directory lists UK accountants by area if you want to talk through the numbers for your own business.

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