UK Corporation Tax Calculator
Calculate UK corporation tax for 2024/25. Includes marginal relief for profits between £50,000 and £250,000.
£
Quick:
£33,750
Corporation Tax
22.5%
Effective Rate
£3,750
Marginal Relief
£116,250
After-Tax Profit
Corporation Tax Calculation
| Component | Amount |
|---|---|
| Taxable Profit | £150,000 |
| Applicable Rate | 25% (main rate) |
| Tax at Full Rate | £37,500 |
| Marginal Relief Deducted | -£3,750 |
| Lower Threshold | £50,000 |
| Upper Threshold | £250,000 |
| Corporation Tax Due | £33,750 |
UK Corporation Tax Rates (2024/25)
Rate Structure
Small Profits Rate: 19% on profits up to £50,000
Main Rate: 25% on profits above £250,000
Marginal Relief: applies between £50,000 and £250,000
Marginal Relief = (Upper Limit - Profits) / (Upper - Lower) × (Main Rate - Small Rate) × Profits
= (250,000 - P) / 200,000 × 6% × P
Main Rate: 25% on profits above £250,000
Marginal Relief: applies between £50,000 and £250,000
Marginal Relief = (Upper Limit - Profits) / (Upper - Lower) × (Main Rate - Small Rate) × Profits
= (250,000 - P) / 200,000 × 6% × P
Example
£150,000 profit (no associated companies):
Tax at 25% = £37,500
Marginal Relief = (£250,000 - £150,000) / £200,000 × 6% × £150,000
= 50% × 6% × £150,000 = £4,500
Corporation Tax = £37,500 - £4,500 = £33,000
Effective Rate = 22.0%
Tax at 25% = £37,500
Marginal Relief = (£250,000 - £150,000) / £200,000 × 6% × £150,000
= 50% × 6% × £150,000 = £4,500
Corporation Tax = £37,500 - £4,500 = £33,000
Effective Rate = 22.0%
Extended
Small Profits vs Main Rate Comparison
Visual breakdown of how marginal relief works across different profit levels
Corporation Tax at Different Profit Levels
| Profit | Tax | Effective Rate | Marginal Relief |
|---|
Assumes no associated companies. Marginal rate in the £50K–£250K band is 26.5%.
Frequently Asked Questions
What is the UK corporation tax rate for 2024?
From April 2023, the main rate is 25% for companies with profits over £250,000. The small profits rate is 19% for companies with profits of £50,000 or less. Marginal relief applies for profits between £50,000 and £250,000.
What is marginal relief?
Marginal relief reduces the tax burden for companies with profits between £50,000 and £250,000. The effective marginal rate in this band is approximately 26.5%. The relief provides a smooth transition between the small profits rate and the main rate.
Are the thresholds affected if there are associated companies?
Yes. The £50,000 and £250,000 thresholds are divided by the number of associated companies plus one. So if you have one associated company, each threshold is halved.
When is corporation tax due?
For smaller companies, corporation tax is due 9 months and 1 day after the end of the accounting period. Large companies with profits over £1.5M must pay in quarterly instalments during the accounting period.
What expenses are deductible from corporation tax?
Most business expenses incurred wholly and exclusively for business purposes are deductible: salaries, rent, utilities, professional fees, depreciation allowances, R&D expenditure, and interest costs (subject to restrictions).