Ltd vs Sole Trader UK: Tax Compared With Examples

The £50,000 as a sole trader

Sole traders pay income tax on profits plus Class 4 National Insurance. (Class 2 NICs were abolished in April 2024, so there's one less line on the bill than the old guides show.) Here are the 2026/27 figures:

1. Profit: £50,000 2. Personal allowance: −£12,570 → taxable profit £37,430 3. Income tax at 20%: £7,486 4. Class 4 NICs at 6% on profits between £12,570 and £50,270: 6% × £37,430 = £2,245.80 5. Total tax + NICs: £9,731.80 6. Left in hand: £40,268.20

Simple, single calculation, paid through Self Assessment. No payroll, no corporation tax return, no dividend paperwork. That simplicity has a value the numbers don't show.

The £50,000 through a limited company

Now the same £50,000 earned through a Ltd, extracted with the classic optimal split: £12,570 salary (using the personal allowance) plus the rest as dividends. 2026/27 rates: corporation tax 19% on profits up to £50,000, dividend tax 10.75% basic / 35.75% higher, £500 dividend allowance.

1. Company profit: £50,000 2. Director's salary: £12,570 (deductible expense, no income tax, no employee NICs) 3. Taxable company profit: £50,000 − £12,570 = £37,430 4. Corporation tax at 19%: £7,111.70 5. Available for dividends: £37,430 − £7,111.70 = £30,318.30 6. Dividend allowance: first £500 at 0% → taxable dividends £29,818.30 7. Total income £42,888.30 (£12,570 salary + £30,318.30 dividends) sits entirely within the basic-rate band (£50,270) 8. Dividend tax at 10.75%: £29,818.30 × 10.75% = £3,205.47 9. Total tax: £7,111.70 + £3,205.47 = £10,317.17 10. Left in hand: £50,000 − £10,317.17 = £39,682.83 (before employer NICs on the salary)

The Ltd route costs £585 more than sole trader at £50,000 — and that's before employer NICs (15% on salary above £5,000 = £1,135.50, though most small companies wipe this out with the £10,500 Employment Allowance) and accountancy fees, which run £800–£1,500 a year higher for a Ltd.

If your profits sit between £50,000 and £250,000, marginal relief tapers the corporation tax rate between 19% and 25% — check where you land with the UK Corporation Tax & Marginal Relief Calculator before assuming the headline 25% applies.

Where the crossover actually sits

Run the same comparison at higher profits and the picture flips. At £80,000 of profit:

Sole trader: income tax £7,540 + 40% on £29,730 (£80,000 − £50,270) = £11,892 → £19,432 total income tax. Class 4: 6% × £37,700 = £2,262, plus 2% × £29,730 = £594.60 → £2,856.60. Total: £22,288.60.

Ltd (£12,570 salary + dividends): profit after salary £67,430 → corporation tax 19% = £12,811.70 → dividends £54,618.30. Dividend tax: £500 at 0%; basic band remaining £37,700 at 10.75% = £4,052.75; higher slice (£54,118.30 − £37,700) = £16,418.30 at 35.75% = £5,869.54. Total: £12,811.70 + £9,922.29 = £22,733.99.

Still roughly level at £80k — the 2026 dividend tax rise narrowed the old advantage considerably. The Ltd pulls clearly ahead around £90,000–£100,000 of profit, where the sole trader's 40% income tax + 2% NICs (42%) exceeds the company's combined 19% + 35.75%-on-the-rest effective rate. Below that, the tax argument for incorporating is thin — which surprises people who remember the old days when the Ltd won from £30k up.

The non-tax reasons that actually decide it

Limited liability. This is the real reason most people incorporate. As a sole trader, your personal assets — house, savings — are on the line if the business fails or gets sued. A Ltd ring-fences them. If you have employees, take on contracts with liability clauses, or work in a litigious sector, this alone justifies the switch regardless of the tax maths.

Credibility and contracts. Some clients, especially corporates and public sector, prefer or require Ltd suppliers. IR35 works differently too: operating through a Ltd doesn't dodge IR35, but being a sole trader doesn't help with it either.

Profit retention. A Ltd can leave profits in the company taxed at 19–25%, to be extracted later in a lower-income year or invested. A sole trader is taxed on everything in the year it's earned, like it or not. If you don't need all the income now, the Ltd is a timing machine.

Admin and cost. Sole trader: one Self Assessment return. Ltd: annual accounts, corporation tax return, confirmation statement, payroll, dividend paperwork — and an accountant's bill to match. Budget an extra £1,000+ a year. For a side hustle making £20k, that's a terrible trade.

Mortgages. Lenders understand salaries; they scrutinise dividends and retained profits. The newly incorporated often find borrowing harder for the first two years until they have company accounts to show. Time the switch away from remortgage season.

IR35: the elephant in the room

None of the above matters if HMRC decides you're a disguised employee. IR35 (the off-payroll working rules) targets contractors working through personal service companies who look, to HMRC, like employees. If you're caught, the company's income is subject to deemed employment taxes — wiping out most of the Ltd advantage at a stroke.

Since April 2021, medium and large private-sector clients decide your IR35 status, not you — and most decide "inside IR35" defensively. Genuinely independent contractors (multiple clients, control over how work is done, financial risk) are usually fine; single-client, supervised, nine-to-five contractors usually aren't. The status determination statement from your client is the document that matters — read it, challenge it if the facts are wrong, and never sign a contract that says one thing while you do another.

Small-company clients are the exception: if your client is small, you still determine your own status. That's one more reason the client mix matters as much as the profit figure when choosing a structure.

A practical note: many contractors now operate hybrid — Ltd for the genuinely independent work, umbrella or PAYE for the inside-IR35 contracts. It's messier, but it matches the tax treatment to the reality of each engagement instead of forcing one structure onto everything.

The verdict: a decision tree

• Under £40k profit: stay sole trader. The tax is lower, the admin is trivial, the savings don't justify the cost.
• £40k–£90k: it's a coin flip on tax — decide on liability, credibility, and whether you want to retain profits. Most people incorporate in this band for non-tax reasons.
• Over £90k–£100k: incorporate. The tax saving is real and growing, and the admin cost is rounding error.
• With employees or contractual liability: incorporate regardless of profit. The liability shield is worth more than any tax calculation.

And revisit yearly. The crossover moves with every Budget — the 2026 dividend rise moved it £20k higher than it was. What was right in 2023 may not be right now. A quick annual comparison takes an hour and can save thousands — put it in the diary alongside the accounts deadline, and run the numbers before every Budget, not after.