UK Corporate Tax Calculator
Enter your company's taxable profits to instantly calculate UK corporation tax with small profits rate, main rate, and marginal relief for 2023/24 onwards.
Tax Inputs
Your company's profits chargeable to corporation tax for the accounting period.
Number of companies associated with yours under HMRC rules. Thresholds are divided equally among all companies.
2023/24 rates: 19% (profits up to £50k), 25% main rate (profits above £250k), marginal relief taper in between. Thresholds divided by number of associated companies + 1.
Enter taxable profits to see your UK corporation tax breakdown.
Corporation Tax Liability
£0
—
Effective Rate
0.00%
Marginal Relief
£0
After-Tax Profit
£0
| Item | Amount | % of Profits |
|---|---|---|
| Taxable Profits | — | 100.00% |
| Gross Tax at Main Rate (25%) | — | — |
| Marginal Relief | — | — |
| Tax Liability | — | — |
| After-Tax Profit | — | — |
Summary
Enter your company's taxable profits to instantly calculate UK corporation tax with small profits rate, main rate, and marginal relief for 2023/24 onwards.
How it works
- Enter your company's taxable profits for the accounting period.
- If you have associated companies, enter the count to adjust the profit thresholds.
- Click Calculate to see your corporation tax liability.
- Review the rate band applied — small profits (19%), marginal relief, or main rate (25%).
- Check the marginal relief amount and effective tax rate in the breakdown.
- Click Reset to clear all fields and start over.
Use cases
- Estimating quarterly corporation tax payments for HMRC.
- Modelling after-tax profit in a business plan or investor pitch.
- Understanding the marginal relief taper between £50,000 and £250,000.
- Comparing tax liability across different profit scenarios.
- Assessing the impact of associated companies on profit thresholds.
- Quick sanity-check before filing a Company Tax Return (CT600).