Corporation Tax with marginal relief calculator UK
Estimate 2026 Corporation Tax for a qualifying company over a full 12-month accounting period. Check the formula, worked example and limits before using your own figures.
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Estimated Corporation Tax
Inputs changed. Select Calculate result to update your estimate.
Use your actual figures. Any prefilled price, fee, rate or return is an editable illustration, not a current product quote. Full 12-month period only. UK-resident non-ring-fence company eligible for small profits treatment; excludes close investment-holding companies, special regimes, losses and other adjustments. Short periods need different limits.
How the corporation tax with marginal relief calculator uk works
Use 19% below the adjusted lower limit, 25% above the upper limit; otherwise deduct 3/200 × (upper − augmented profit) × taxable/augmented profit.
UK data and rules
Corporation Tax year starting 1 April 2026 data · Checked 16 October 2026. Rules are a dated snapshot, not a live feed.
Read about data coverage and updates
Worked example: corporation tax with marginal relief
This illustration uses the calculator’s example inputs. It is not a quote or a recommended financial decision.
- Taxable total profits (£)
- 100,000
- Augmented profits including relevant distributions (£)
- 100,000
- Other associated companies
- 0
Estimated Corporation Tax: £22,750.00
Use 19% below the adjusted lower limit, 25% above the upper limit; otherwise deduct 3/200 × (upper − augmented profit) × taxable/augmented profit.
Corporation Tax with marginal relief: questions answered
What does the corporation tax with marginal relief calculation include?
Use 19% below the adjusted lower limit, 25% above the upper limit; otherwise deduct 3/200 × (upper − augmented profit) × taxable/augmented profit. Use your actual figures. Any prefilled price, fee, rate or return is an editable illustration, not a current product quote. Full 12-month period only. UK-resident non-ring-fence company eligible for small profits treatment; excludes close investment-holding companies, special regimes, losses and other adjustments. Short periods need different limits.
Using your result
Example inputs are a starting point. Replace them with your figures and select Calculate result. Results are rounded for display; calculations use unrounded values.
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