UK Corporation Tax Rates and Thresholds 2025/26

The UK Corporation Tax system for the 2025/26 tax year uses a tiered structure based on your company's taxable profits. Companies with profits of £50,000 or less pay a 19% small profits rate, while those with profits over £250,000 pay the 25% main rate. Businesses with profits between these thresholds use marginal relief to calculate their tax liability.

Current rates and thresholds

The following table outlines the Corporation Tax structure for the financial year 2026 (which covers the 2025/26 period).

| Profit Level | Tax Rate | | :--- | :--- | | Profits up to £50,000 | 19% (Small Profits Rate) | | Profits between £50,000 and £250,000 | Marginal Relief applies | | Profits over £250,000 | 25% (Main Rate) |

When they apply

These rates apply to the financial year 2026, which runs from 1 April 2026 to 31 March 2027. For the 2025/26 tax year, the same structure remains in place. If your company's accounting period does not align with the financial year, you may need to apportion your profits across different rates. Always confirm the current rate on the official government website before filing your CT600 (the Corporation Tax return form).

How to calculate

Calculating your tax involves determining your taxable profits after allowable expenses.

1. Calculate your total taxable profit for the accounting period.
2. If your profit is £50,000 or less, apply the 19% rate.
3. If your profit is over £250,000, apply the 25% rate.
4. If your profit falls between £50,000 and £250,000, use the HMRC Marginal Relief calculator. This ensures you do not pay the full 25% on every pound of profit immediately after crossing the £50,000 threshold.

Note that if you have associated companies, these thresholds are divided by the number of companies, which lowers the point at which you reach the higher rate. You must report these figures accurately on your CT600.