Corporation Tax & Marginal Relief 2026/27
For a 12-month period with no associated companies, the first £50,000 of taxable profit is taxed at 19%. The next £200,000 is effectively taxed at 26.5%, so the overall rate gradually rises to 25%.
Enter your taxable profit to estimate the bill and your overall tax rate. You can also allow for associated companies and a shorter accounting period.
Your Inputs
What this changes
Profit after allowable expenses and reliefs, before Corporation Tax. For 12 months with no associated companies, the rate is 19% up to £50,000 and 25% from £250,000. Between those limits, each extra £1 of profit adds 26.5p to the tax bill; the overall rate is lower than 26.5%.
What this changes
Other companies under common control. The £50,000 lower and £250,000 upper limits are divided by (1 + number of associates), pulling the marginal-relief band downward. With one associate the band runs from £25,000 to £125,000; with three it runs from £12,500 to £62,500.
Enter a whole number of months from 1 to 12. Accounts covering more than 12 months need separate Corporation Tax returns.
What this changes
This estimate accepts 1-12 whole months. A 6-month period halves the profit limits. Corporation Tax accounting periods cannot exceed 12 months; longer accounts need separate returns. Exact dates are needed for the final calculation.
Corporation Tax liability
Rates current for tax year 2026/27
These calculators are diagnostic tools intended to give you an initial estimate. They are not a substitute for personalised advice on your specific circumstances. Figures depend on the inputs you provide and on tax rules that change over time. Speak to us before acting on any result.
A CIMA Chartered Management Accountant will review your details and send you a tailored breakdown.
Estimate for a company eligible for the small profits rate and Marginal Relief, with no exempt distributions added to profits for the relief calculation. Short periods use months divided by 12 as an approximation; the return uses the actual dates. Limits also depend on associated companies. See HMRC's accounting period guidance.
Check the profit figure first
Corporation Tax is charged on taxable profit, not the cash left in the bank. The figure should already allow for salary, employer pension contributions, capital allowances, disallowable costs, any losses brought forward and timing differences at year-end.
The Marginal Relief limits are reduced when the company has associated companies. One associated company halves the £50,000 and £250,000 thresholds. The 26.5% marginal rate then applies to extra profit between those lower limits; it is not the rate on the whole profit figure.
Use the calculator to test the size of the Corporation Tax bill, then check the working against the accounts before making pension, dividend or capital spending decisions.