UK Sole Trader vs Limited Company: Which to Choose

UK business owners face a choice between operating as a sole trader (or partnership) and incorporating as a limited company. The decision shapes tax position, administration, liability exposure, and credibility with clients. Neither is universally better - the right choice depends on profit level, family tax position, growth plans and personal preferences.

This guide compares the two structures across the main dimensions, with worked examples at different profit levels showing where each is more tax-efficient.

Sole trader: simplicity and personal liability

A sole trader is an individual operating a business in their own name. There is no legal distinction between the person and the business: profits are personal income, debts are personal debts, contracts are with the individual. Setup is simply registering with HMRC by 5 October following the tax year of starting.

Administration is minimal. Annual SA return covers business income through the SA103 pages. No company accounts, no Companies House filings, no director duties. Bookkeeping for tax purposes is sufficient; formal financial statements are not required.

Personal liability is the main risk. Where the business runs up debts beyond its ability to pay, creditors can pursue the trader personally including against their home and savings. Public liability insurance and professional indemnity insurance address some risk; personal asset risk is harder to mitigate.

Tax: business profits are taxed at the trader's marginal income tax band plus Class 4 NI at 6%/2%. Profits stack with other personal income; a sole trader with significant employment income may find self-employed profits all taxed at higher rate.

Limited company: separate entity and corporation tax

A limited company is a separate legal entity. Owners hold shares; the company contracts in its own name; profits and losses sit with the company. Limited liability protects shareholders' personal assets from business debts (except where personal guarantees are signed).

Tax: corporation tax at 19% on profits up to GBP 50,000 (small profits rate), 25% on profits above GBP 250,000 (main rate), with marginal relief producing an effective 26.5% on the GBP 50,000-GBP 250,000 band. The company's profits are taxed at the company level first; further tax applies when directors extract money.

Extraction routes: salary (deductible by company but attracts PAYE and NI), dividends (paid from post-tax profits, taxed at 8.75%/33.75%/39.35% above the GBP 500 dividend allowance), pension contributions (deductible by company, tax-deferred for the director). Most director-shareholders use a combination.

Administration: annual accounts filed at Companies House and HMRC, confirmation statement filed at Companies House annually, corporation tax return filed annually, monthly or quarterly payroll (where salary is paid). Bookkeeping requirements are more formal than for a sole trader.

Tax comparison at typical profit levels

Worked example A: GBP 30,000 of profit. Sole trader: income tax GBP 3,486 (20% above PA) + Class 4 NI GBP 1,046 = GBP 4,532. Take-home GBP 25,468. Limited company: corporation tax GBP 5,700 (19% of GBP 30,000), GBP 24,300 post-tax. Director takes GBP 12,570 as salary (no income tax, minimal NI) + GBP 11,730 as dividends. Dividends: GBP 500 allowance + GBP 11,230 at 8.75% = GBP 983. Total tax GBP 5,700 + GBP 983 = GBP 6,683. Take-home GBP 23,317. Sole trader wins by around GBP 2,150 at this level.

Worked example B: GBP 60,000 of profit. Sole trader: tax GBP 11,432, Class 4 NI GBP 2,455, total GBP 13,887. Take-home GBP 46,113. Limited company: corporation tax GBP 11,400 (19% on first GBP 50,000, marginal on remaining GBP 10,000) approximately GBP 11,950. Post-tax GBP 48,050. Director: salary GBP 12,570, dividend GBP 35,480. Dividend tax: GBP 500 allowance, GBP 34,980 at 8.75% = GBP 3,061. Total tax GBP 11,950 + GBP 3,061 = GBP 15,011. Take-home around GBP 44,989. Sole trader narrows the gap or wins by small amount.

Worked example C: GBP 100,000 of profit. Sole trader: tax GBP 27,432, NI GBP 3,455 (2% on the slice above UEL), total GBP 30,887. Take-home GBP 69,113. Limited company: corporation tax around GBP 22,750. Post-tax GBP 77,250. Director: salary GBP 12,570, dividend GBP 64,680. Dividend tax (some at 8.75%, much at 33.75%): around GBP 18,500. Total tax GBP 22,750 + GBP 18,500 = GBP 41,250. Limited company actually higher in this simple model. The crossover depends on extraction pattern, pension contributions, and family tax planning.

Practical action: pure tax comparisons at any profit level show only part of the picture. Pension contributions through the company (deductible by company, tax-deferred for director) shift the equation. Family income splitting (employing spouse) shifts it further. Modelling against the specific situation is essential before incorporating.

When incorporation makes sense

Below around GBP 30,000-40,000 of profit, sole trader is typically simpler and similarly or more tax-efficient. The administration burden of a limited company is not justified by tax savings.

Around GBP 40,000-100,000 of profit, the tax comparison is closer. The deciding factors become non-tax: liability protection, professional credibility (some clients prefer working with limited companies), ability to retain profits in the company at corporation tax rate, and family tax planning (spouse shareholding).

Above GBP 100,000 of profit, the limited company often becomes tax-efficient through pension contributions and profit retention. The 60% effective marginal rate on personal income GBP 100,000-125,140 (PA taper) makes retention inside the company at 19-26.5% corporation tax attractive.

Other triggers: a client requires limited-company status (common in IT contracting), the business has significant fixed assets (vehicles, equipment) that need depreciation treatment, the owner is planning a future sale (limited company shares can attract Business Asset Disposal Relief at 14%-18%), or there are external investors.

Liability protection and personal guarantees

The headline advantage of limited company status is limited liability: shareholders' personal assets are protected from business debts. In practice, the protection has limits. Personal guarantees from directors (commonly required by lenders, landlords, large suppliers) override the limited liability for the guaranteed obligations.

Where a director has signed personal guarantees on a company loan, they remain personally liable for that loan even if the company fails. Similarly for personally-guaranteed lease obligations. Many small companies in their first few years effectively have limited protection because the founder has guaranteed key obligations.

Insurance bridges some gaps. Professional indemnity insurance covers most professional negligence claims; public liability covers third-party injury or property damage; directors and officers (D&O) insurance covers director-specific risks. The cost varies by business type but typically GBP 500-3,000 a year for small businesses.

Practical action: limited liability is not absolute, and the protection should not drive incorporation in isolation. Where liability protection is the only motivator, insurance often provides better-targeted protection than incorporation. Combining incorporation with appropriate insurance gives the strongest position.

Switching from sole trader to limited company

Incorporating an existing sole trader business involves transferring the business to a new limited company. The transfer is a chargeable disposal for CGT purposes on assets (goodwill, equipment, customer lists), though section 162 TCGA 1992 allows incorporation relief deferring the gain into the shares received in exchange.

The new company is registered at Companies House (online, around GBP 12-50 fee depending on speed). The director's role is confirmed; the shareholding is set; the registered office address is established. Bank account in the company's name is opened separately.

HMRC re-registration: the sole trader's SA continues for the final year of self-employment; the new company registers for corporation tax. PAYE registration is required if the company will employ anyone (including the director). VAT registration may transfer or restart depending on circumstances.

Worked example: a sole trader designer with GBP 80,000 of profit decides to incorporate from 6 April 2027. Pre-incorporation: final SA return for 2026/27 covers sole trader period to 5 April 2027. Post-incorporation: company files corporation tax return for the first accounting period; the designer becomes a director-shareholder. Bookkeeping, banking and contracts all transition.

Pension contributions through a limited company

One of the major tax advantages of limited company status for owner-directors is employer pension contribution. The company pays into the director's pension as a deductible business expense, with no employer NI on the contribution. The director receives the contribution tax-deferred in their pension.

The annual allowance of GBP 60,000 applies to total pension contributions including employer payments. For a higher-rate director, a GBP 40,000 company contribution saves corporation tax of GBP 7,600 (19% on GBP 40,000), saves the director GBP 16,800 of dividend tax that would have applied if the GBP 40,000 had been distributed as dividend (33.75% on GBP 40,000), and grows tax-free until retirement.

The total tax saving on a GBP 40,000 pension contribution versus dividend extraction can exceed GBP 24,000 for a higher-rate director. This is the largest single tax efficiency of limited company status for owner-directors, particularly for higher earners.

Practical action: pension contributions need to be wholly and exclusively for the trade to be deductible at the company level. A 'reasonable' level relative to director's role and contribution is the test. Excessive contributions (well beyond what would be paid as salary) may be challenged by HMRC; typical practice is for the contribution not to exceed the salary in any year.

Companies House compliance for limited companies

Limited companies have annual compliance obligations to Companies House separate from HMRC. Annual accounts must be filed within 9 months of the accounting reference date (the company year-end). Confirmation statement (a snapshot of company details, formerly annual return) must be filed within 14 days of the anniversary of incorporation or the prior confirmation statement.

Companies House fees: confirmation statement GBP 34 online (GBP 62 paper) annually. Accounts are filed at no separate fee but require professional preparation in most cases - small company abridged accounts typically GBP 500-1,500 in accountancy fees.

Late filing penalties at Companies House: GBP 150 for up to 1 month late, GBP 375 for 1-3 months, GBP 750 for 3-6 months, GBP 1,500 for over 6 months. Doubled if late in two consecutive years. Persistent failure can result in the company being struck off the register.

Director responsibilities: confirmation that information held at Companies House is correct (registered office, directors, persons of significant control, share capital), annual review of company position, signing of accounts on behalf of the company. Directors' duties under sections 171-177 Companies Act 2006 set a higher legal bar than sole trader self-management.

Family income splitting through limited company

A spouse or civil partner can be a shareholder in a limited company alongside the trading director. Dividends paid to the spouse are taxed at their marginal rate, not the working partner's. Where the working partner is higher-rate and the spouse is basic-rate (or non-taxpayer), the income split saves tax.

The settlements legislation (sections 624-628 ITTOIA 2005) has historically been a concern - HMRC's view in some cases is that dividend payments to a non-working spouse are 'settled income' returnable to the working partner for tax purposes. The Arctic Systems case (Jones v Garnett 2007) provided some protection for shares held in joint family ownership, but the issue remains case-specific.

Practical structures: husband and wife each own 50% of company shares; the company pays dividends pro-rata to shareholding; each spouse's dividend income is taxed at their own marginal rate. Where both partners contribute to the business (one as primary trader, one as administrator or director-support), the structure is generally accepted.

Worked example: a higher-rate working partner with GBP 80,000 of dividends saves GBP 7,500 a year by splitting GBP 30,000 to a basic-rate spouse (dividend tax difference between 33.75% and 8.75% on GBP 30,000). Over 10 years that's GBP 75,000 of tax saved, well worth the structural complexity.

Frequently asked questions

Should I be a sole trader or limited company?

Depends on profit level, family tax position, liability concerns, and growth plans. Below GBP 30,000-40,000 of profit, sole trader is typically simpler and similarly or more tax-efficient. Above GBP 50,000-100,000, the limited company often wins on tax through pension contributions and profit retention. Liability protection from incorporation has practical limits because directors typically sign personal guarantees on key obligations.

How much does a limited company cost to run?

Companies House confirmation statement GBP 13 annually. Accountancy fees for accounts and tax return GBP 1,000-3,000 a year for a small company. Banking GBP 0-100 a year depending on account choice. Insurance GBP 500-3,000 depending on business type. Software (Xero, QuickBooks) GBP 200-500 a year. Total typically GBP 1,500-5,000 a year on top of personal SA costs.

How are limited company directors paid?

Most director-shareholders take a small salary up to the Personal Allowance (GBP 12,570) to use the PA and build NI credits, plus dividends from post-tax profits. Salary is deductible by the company; dividends are paid from profits after corporation tax. Director's loan accounts can also be used short-term but attract specific tax treatment. Pension contributions through the company are typically tax-efficient at the senior director level.

What's corporation tax in 2026/27?

Small profits rate 19% on profits up to GBP 50,000. Main rate 25% on profits above GBP 250,000. Marginal relief produces an effective rate of 26.5% on the band between GBP 50,000 and GBP 250,000. The thresholds are divided by the number of associated companies (broadly companies under common control), so groups have reduced thresholds per company.

Can I switch back from limited company to sole trader?

Yes through dissolution or strike-off of the company, plus restart of sole trader registration. The company's assets are distributed (with tax implications on the distribution - typically dividends or capital distribution under section 1030 CTA 2010). Tax planning for the wind-down matters because distributions can attract significant personal tax. Business Asset Disposal Relief at 14%-18% may apply on the final capital distribution where conditions are met.