Work out exactly what your limited company owes HMRC. Enter your taxable profit and we apply the 19% small profits rate, the 25% main rate, and the marginal relief that smooths the band between £50,000 and £250,000.
Single company · 12-month accounting period
Since April 2023 the UK has had a two-rate Corporation Tax system, and the same structure applies in 2026/27. The rate your company pays depends on the size of its profits, with marginal relief bridging the gap between the two headline rates.
| Profit band | Treatment | Rate |
|---|---|---|
| Up to £50,000 | Small profits rate | 19% |
| £50,001 – £250,000 | Main rate with marginal relief | 19% → 25% |
| Over £250,000 | Main rate | 25% |
Here is how the calculator arrives at the tax on £100,000 of profit:
Profit is taxed after allowable costs, so the main levers reduce taxable profit before the rate applies:
The main rate is 25% on profits over £250,000 and the small profits rate is 19% on profits up to £50,000. Profits in between are taxed at 25% with marginal relief, giving an effective rate that climbs from 19% to 25%.
Marginal relief equals (£250,000 − profit) × the standard fraction of 3/200 for a single company with a full year. It is deducted from the tax charged at 25%, smoothing the jump between the two rates.
About £22,750 — £25,000 at the 25% main rate less roughly £2,250 of marginal relief, an effective rate of 22.75%.
The £50,000 and £250,000 limits are divided by the number of associated companies plus one. Two associated companies, for example, share thresholds of £25,000 and £125,000 each, pushing more profit into the higher rate sooner.
