Business & tax · UK
Corporation Tax Calculator
Work out the corporation tax on your company profits for the financial year from April 2026. We apply the 19% small profits rate, the 25% main rate and Marginal Relief in between, and show your effective rate.
Rates for the financial year from 1 April 2026, for a single standalone company. An estimate to help you plan, not tax advice. Confirm with HMRC or an accountant.
How corporation tax works in 2026/27
Limited companies pay corporation tax on their taxable profits. For the financial year from 1 April 2026 there are two rates and a band in between (unchanged from the previous year):
- Small profits rate, 19%. Profits up to £50,000.
- Marginal Relief, 19% to 25%. Profits between £50,000 and £250,000, where the effective rate tapers up.
- Main rate, 25%. Profits of £250,000 or more.
How Marginal Relief is worked out
In the £50,000 to £250,000 band you do not simply pay 25%. You work out the tax at the main rate, then deduct Marginal Relief of 3/200 of the difference between the £250,000 upper limit and your profit. Take a £100,000 profit: 25% is £25,000, the relief is 3/200 of £150,000, which is £2,250, so the bill is £22,750. The practical effect is a 26.5% marginal rate on each pound of profit inside the band.
Associated companies
If your company is one of a group of associated companies, broadly those under common control, the £50,000 and £250,000 limits are divided by the total number of companies. With one associate the limits halve to £25,000 and £125,000, so a given profit pays more. This calculator assumes a single standalone company with no associates and no exempt distributions.
Common questions
How much is corporation tax in 2026/27?
There are two rates. 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%. Profits between the two get Marginal Relief, which tapers the effective rate up from 19% towards 25%.
What is Marginal Relief?
Marginal Relief smooths the jump between the 19% and 25% rates for profits between £50,000 and £250,000. You work out the tax at 25%, then deduct relief of 3/200 of the difference between £250,000 and your profit. The effect is a 26.5% marginal rate on the slice of profit in that band.
How do I work out corporation tax on £100,000 of profit?
That profit sits in the Marginal Relief band. The tax at 25% is £25,000. The relief is 3/200 of (£250,000 minus £100,000), which is £2,250. So the corporation tax is £22,750, an effective rate of about 22.75%.
Do associated companies change the figure?
Yes. If your company has associated companies (broadly, ones under common control), the £50,000 and £250,000 limits are divided by the total number of companies. With one associate the limits halve to £25,000 and £125,000, so Marginal Relief kicks in sooner. This calculator assumes a single standalone company.
What profit does corporation tax apply to?
It applies to your taxable total profits: your trading profit plus any other income and chargeable gains, after deducting allowable expenses and reliefs such as capital allowances. Enter that final taxable figure, not your turnover.
When is corporation tax due?
For most companies, corporation tax is due nine months and one day after the end of the accounting period, and the company tax return is due twelve months after. Larger companies pay in quarterly instalments.
Do dividends reduce my corporation tax bill?
No. Dividends are paid out of profit after corporation tax, so they do not reduce the tax. What does reduce it are allowable business expenses, and things like directors' salaries and employer pension contributions, because those come off before the profit is taxed. Dividends are then taxed separately on the people who receive them.
About this calculator
Written by the calcd team. We checked the rates, limits and the Marginal Relief method against gov.uk (HMRC). The result is an estimate to help you plan, not tax advice. Your real bill depends on associated companies, the length of your accounting period and any reliefs, so confirm it with HMRC or an accountant. Last updated June 2026.