UK Corporation Tax Calculator (19%–25% Marginal Relief) (2026)
Calculate UK Limited Company Corporation Tax liability with small profits rate (19%), main rate (25%), and marginal relief.
United Kingdom Calculator
Adjust Your Inputs
Move the sliders or type exact numbers. Results update instantly.
Instant Estimate
Your Results
Corporation Tax Due
£28,050
Based on your selected corporation tax uk assumptions. Try different sliders to compare scenarios.
Effective Tax Rate
23.38%
Marginal Relief Saved
£1,950
Profit After Tax
£91,950
These calculations are financial projections and planning estimates, not tax, legal or licensed financial advice. HMRC 2025/2026 statutory rates, NI thresholds, and local council rates apply.
How to Use the Corporation Tax UK
Enter taxable company profit
Input your limited company’s net taxable trading profit after business expenses.
Specify associated companies
Indicate any sister companies under common 51% ownership or control to adjust profit thresholds.
Review tax liability and marginal relief
See your corporation tax due, effective tax rate, and marginal relief savings.
Formula & Calculation Methodology
Tax = Profits × 25% - Marginal Relief Fraction (3/200) × (Upper Limit - Profits)This calculator uses standard United Kingdom financial formulas, IRS thresholds, and amortization schedules. All results compute instantly in your browser with zero data stored or transmitted.
Calculation Examples & Scenarios
Small Business Under £50,000 Profit
£45,000 taxable trading profit, 0 associated companies.
Mid-Tier Company in Marginal Relief Band (£120,000)
£120,000 taxable profit, 0 associated companies.
High-Earning Corporation (£300,000 Profit)
£300,000 taxable profit exceeding the £250,000 upper limit.
Key Benefits
- Applies official HMRC Marginal Relief fraction (3/200) with precision
- Dynamically divides lower and upper thresholds for associated companies
- Helps directors evaluate the tax efficiency of salary vs dividend distributions
Common Use Cases
- UK limited company directors forecasting year-end corporate tax liabilities
- Accountants modeling corporate tax scenarios across group company structures
- Entrepreneurs deciding when to invest in capital allowances before financial year-end
UK Corporation Tax Brackets and Marginal Relief
Companies with annual taxable profits up to £50,000 pay the Small Profits Rate of 19%. Companies with profits above £250,000 pay the Main Rate of 25%. Between £50,000 and £250,000, Marginal Relief phases in gradually, creating an effective marginal tax rate of 26.5% on profits within this middle taper band.
Marginal Relief ensures businesses earning slightly above £50,000 do not experience a sharp cliff-edge tax penalty on their entire profit base.
Impact of Associated Companies
Under HMRC rules, if your company has associated companies (companies controlled by the same person or group), the £50,000 and £250,000 profit thresholds are divided equally by the total number of associated companies plus your own, reducing the band limits accordingly.
Frequently Asked Questions
Companies with taxable profits under £50,000 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 qualify for Marginal Relief, creating an effective marginal rate of 26.5% in the taper band.
Marginal Relief provides a gradual sliding scale discount so companies earning just over £50,000 do not immediately jump to a full 25% flat tax on all profits.
The £50,000 and £250,000 thresholds are divided equally by the number of associated companies under common control (e.g., with 1 associated company, the thresholds become £25,000 and £125,000).
Corporation Tax must be paid electronically to HMRC 9 months and 1 day after the end of your company accounting period.
Yes. Director salaries are an allowable business expense that reduces taxable trading profits, whereas dividend distributions are paid from post-tax profits.
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