UK Corporation Tax Calculator
Work out your Corporation Tax bill for 2026/27, including marginal relief between £50,000 and £250,000 profit.
Disclaimer: This calculator gives an estimate based on standard rates and assumes no exempt distributions. Always confirm your final liability with an accountant or HMRC.
Company Profit Details
2026/27 Corporation Tax Rates
| Profit Band | Rate |
|---|---|
| Up to £50,000 | 19% (small profits rate) |
| £50,001 - £250,000 | 25% with marginal relief (effective 19%-25%) |
| Over £250,000 | 25% (main rate) |
Quick Reference
Standard fraction: 3/200
Marginal relief formula:
(Upper Limit − Profits) × 3/200
Thresholds divide by:
1 + number of associated companies, then pro-rate for periods under 12 months.
Frequently Asked Questions
Since 1 April 2023, companies with profits of £50,000 or less pay the small profits rate of 19%. Companies with profits over £250,000 pay the main rate of 25%. Profits between £50,000 and £250,000 pay 25% reduced by marginal relief, which tapers the effective rate smoothly between 19% and 25%.
Marginal relief reduces your Corporation Tax bill if your profits fall between the £50,000 lower limit and £250,000 upper limit, so you don't face a sudden jump from 19% to 25%. HMRC's formula is: Marginal Relief = (Upper Limit − Profits) × (Profits ÷ Profits) × 3/200, which this calculator applies automatically.
If your company has associated companies (broadly, companies under common control), the £50,000 and £250,000 thresholds are divided by the total number of associated companies plus one. For example, with one associated company (two companies total), the thresholds become £25,000 and £125,000 each.
The £50,000 and £250,000 thresholds are also pro-rated for accounting periods shorter than 12 months. A 6-month accounting period, for instance, would use thresholds of £25,000 and £125,000 (before any associated company adjustment).
No. This tool provides an estimate based on standard HMRC rates and the marginal relief formula for a single trade with no exempt distributions. Your actual liability may differ if you have capital allowances, R&D claims, patent box relief, or other adjustments - always confirm figures with an accountant or HMRC.