Sole Trader vs Limited Company Calculator

A sole trader pays Income Tax and National Insurance directly on all business profits. The tax rates are personal rates: 20%/40%/45% IT bands plus Class 4 NI (6%/2%) — Class 2 NI was abolished in April 2024. Setup is immediate—register with HMRC and start trading. There is no legal separation between you and the business, meaning personal assets are exposed to business liabilities. Accounting requirements are minimal: simple income/expenses records and an annual Self Assessment return.

A limited company pays Corporation Tax on profits at 19% (profits under £50,000) scaling to 25% (profits over £250,000), with marginal relief between those thresholds. The director/shareholder then extracts profits via a combination of salary and dividends. This two-stage extraction (CT then dividend tax) is often cheaper than sole trader rates at higher profit levels because dividends avoid National Insurance entirely. However, the company must file annual accounts with Companies House, maintain statutory registers, and comply with more complex regulatory obligations.

The crossover point where a limited company becomes more tax-efficient than sole trading typically falls between £30,000 and £45,000 of annual profit, depending on the director's other income and personal circumstances. Below this level, the administrative cost and complexity of a limited company often outweigh the modest tax saving. Above £50,000 profit, the combined CT plus dividend tax route usually saves several thousand pounds per year compared with sole trader IT and NI. Other factors include liability protection, pension contribution options, and the perceived credibility of a limited company structure.

Tax comparison: sole trader vs limited company 2026/27. £30,000 profit: sole trader pays £4,884 (income tax + NI); Ltd company pays Corporation Tax £5,700 + dividend tax £980 = £6,680 — sole trader £1,800 better. £50,000 profit: sole trader £11,440; Ltd £8,030 + dividend tax £2,318 = £10,348 — Ltd £1,092 better. £80,000: sole trader £24,892; Ltd £19,360 + dividend tax £3,978 = £23,338 — Ltd £1,554 better. £100,000: sole trader £33,032; Ltd £25,000 + dividend tax £4,978 = £29,978 — Ltd £3,054 better.

When limited company wins clearly. Above £45,000 profit: limited company typically saves £1,000-£5,000+/year tax. Plus pension contributions through company (tax-free, no NI either side). Plus limited liability (assets protected if business fails). Plus separate legal entity = more professional image to clients. Plus easier to add shareholders/partners. Plus business asset purchases through company can reduce dividend extraction needs. Salary sacrifice through Ltd company: cycle-to-work, EV, gym etc tax-efficient.

When sole trader is better. Profits under £40,000: simpler admin saves £1,200-£2,400/year accounting + £500+ time. Total cost of Ltd company: incorporation £200-£500; annual accounts £1,000-£1,800; Companies House filings; personal tax return on dividends; ongoing director responsibilities. Sole trader: one Self Assessment annually, lower admin burden. Best for: solo professionals (consultants, freelancers, contractors); businesses under £45-50k profit; those starting up testing market.

IR35 and contractor implications. IR35 (off-payroll working rules): catches limited company contractors who are 'employees in disguise'. Inside IR35: must pay tax as employee — eliminates Ltd company tax advantage. Outside IR35: free to use Ltd company tax efficiency. Since April 2021: medium/large clients determine IR35 status; small clients (<£10.2M turnover) — contractor decides. IR35 status affects Ltd company calculation dramatically. Sole trader: NOT subject to IR35 (different rules apply for status determination).

Switching from sole trader to limited company. Best time: when profit consistently above £40-£45k (Ltd tax advantage exceeds admin costs). Process: register Ltd company at Companies House (£12-£100); transfer existing business assets (goodwill, equipment) to company; close sole trader business; first Ltd company year-end accounts. Tax considerations: Incorporation relief (CGT deferral on business assets); SDLT on transferring property (5% surcharge applies for BTL portfolios). Use accountant for transition — costs £500-£2,000 but avoids costly mistakes. Don't switch back and forth — choose carefully.