£100,000 self-employed is £69,311 after tax
On £100,000 of trading profit you pay £27,432 in income tax and £3,257 in Class 4 National Insurance. That is £30,689 in total, leaving £69,311 — an effective rate of 31%, well below the headline band rate because the first £12,570 is untaxed. Figures for 2026/27, checked 28 August 2026.
| Trading profit | £100,000.00 |
| Income tax | −£27,432.00 |
| Class 4 NI (6% on £12,570–£50,270, 2% above) | −£3,256.60 |
| Take-home | £69,311.40 |
| Per month | £5,775.95 |
Against £100,000 as a salary
Income tax is the same either way — £27,432 — because it does not care how you earned the money. National Insurance is where they part. An employee on £100,000 pays £4,011 in Class 1; you pay £3,257 in Class 4, which is £754 less. That gap is the whole of the tax advantage, and it buys you no holiday pay, no sick pay and no employer pension contribution — which are worth considerably more than £754 to most people.
Budget for £46,033 in your first January. A bill of £30,689 is over the £1,000 threshold, so HMRC also wants two payments on account of £15,344 towards next year. The first falls due on 31 January with the balancing payment, the second on 31 July. Nobody warns you about this in year one.
Put your own figure in with the self-employed tax calculator. See what £100,000 looks like as a salary if you are weighing a job against it. Contracting through a company instead is priced by the outside IR35 calculator.
Nearby profits
How much tax will I pay on £100,000 self-employed?
£30,689 in total — £27,432 income tax plus £3,257 Class 4 National Insurance. That leaves £69,311, an effective rate of 31%.
Is £100,000 self-employed better or worse than the same salary?
Better, on National Insurance. An employee on £100,000 pays £4,011 in Class 1, against £3,257 in Class 4 here — £754 less. Income tax is identical at £27,432, because it does not care how the money was earned. What self-employment does not buy you is holiday pay, sick pay or an employer pension contribution.
Do I have to make payments on account on £100,000?
Yes. Your bill of £30,689 is over the £1,000 threshold, so HMRC asks for two payments on account of £15,344 each towards next year — the first due 31 January alongside this year's balancing payment, the second on 31 July. In your first year that means paying roughly £46,033 in one January.
Is this profit or turnover?
Profit — turnover minus allowable expenses. If your turnover is under £1,000 you may not need to report it at all, and above that you can deduct the £1,000 trading allowance instead of expenses if that comes to more.
Rates for 2026/27 from gov.uk, checked 28 August 2026. Last updated 28 September 2026. Not tax advice.