Corporation tax calculator
Corporation tax is charged at 19% on profits up to £50,000 and 25% on profits of £250,000 or more, under gov.uk's Corporation Tax rates and reliefs guidance, with marginal relief smoothing the rate in between. This estimates the bill, the effective rate and the marginal rate on your profit.
What are the corporation tax rates?
Corporation tax has two headline rates, set out on gov.uk's Corporation Tax rates and reliefs page. Profits up to £50,000 are taxed at the small-profits rate of 19%. Profits of £250,000 or more are taxed at the main rate of 25% on the whole amount. The band between the two limits is where the main rate is charged and then reduced by marginal relief, so the effective rate rises smoothly rather than jumping.
How does marginal relief work?
Marginal relief equals 3/200 of the difference between the £250,000 upper limit and the profit, under gov.uk's Marginal Relief for Corporation Tax guidance. Because of the way this tapers, an extra pound of profit in the £50,000 to £250,000 band is taxed at an estimated 26.5%, higher than the 25% main rate. That marginal rate is worth checking before deciding whether to bring profit forward or push it into the next accounting period.
How much corporation tax on £90,000 profit?
Take a company with £90,000 of taxable profit, which sits in the marginal band. The calculation starts at 25% of £90,000, which is £22,500, less marginal relief on the £160,000 gap up to £250,000. That leaves an estimated bill of about £20,100, an effective rate of 22.3%. The company would be left with an estimated £69,900 to reinvest or pay out.
Common questions
What are the corporation tax rates?
A small-profits rate of 19% applies to taxable profits up to £50,000. The main rate of 25% applies from £250,000. Between those two figures the main rate is charged and then cut by marginal relief, which produces a gradual climb from 19% up to 25%.
How does marginal relief work?
For profits between £50,000 and £250,000 you calculate tax at 25%, then subtract relief equal to 3/200 of the gap between £250,000 and your profit. The effect is a marginal rate of 26.5% on each pound in that band, which is why the effective rate rises faster than you might expect.
How much corporation tax on £90,000 profit?
A £90,000 profit falls in the marginal relief band. The bill is about £20,100, an effective rate of 22.3%. Each extra £1 of profit in this band is taxed at 26.5%.
What are associated companies?
If you control other companies, the £50,000 and £250,000 limits are divided between them. Two associated companies each get a £25,000 lower limit and a £125,000 upper limit, so profits hit the higher rates sooner. This tool assumes a single company with no associates.
Is this the same across the UK?
Yes. Corporation tax is set by the UK government and applies to companies in all four nations. Unlike income tax, there is no separate Scottish rate.
Sources & Rate Verification
Rates verified against official statutory guidance on 6 September 2026.