UK Limited Company Tax Calculator
Estimate corporation tax, post-tax profit, and a simple dividend tax view for a UK limited company.
Assumes standard UK corporation tax structure (small profits 19%, main rate 25%, marginal relief in between). For planning only.
How this ltd company tax calculator UK works
If you run a UK limited company, your first tax layer is normally corporation tax on taxable profits. This calculator gives a practical estimate using the current structure:
- 19% small profits rate up to the lower limit
- 25% main rate above the upper limit
- Marginal relief between limits
It also gives a simplified dividend tax estimate so you can see a rough take-home picture after company tax.
What counts as profit for corporation tax?
In simple terms, this calculator uses:
Taxable profit = Turnover - allowable expenses - director salary - employer pension contributions
This mirrors basic company bookkeeping logic, but real accounts can include more adjustments (capital allowances, disallowable costs, brought-forward losses, R&D rules, group relief, and more).
Associated companies matter
In the UK, profit limits for small profits and main rates are divided by the number of associated companies (including your own). That means connected businesses can reduce your tax bands and move you into higher corporation tax sooner. This calculator includes an associated-company field for that reason.
Example scenario
Imagine a company with:
- £120,000 turnover
- £20,000 allowable expenses
- £12,570 salary
- £0 employer pension
Estimated taxable profit is £87,430. With no associated companies, that falls in the marginal relief zone, so the effective corporation tax rate lands between 19% and 25%.
Using this calculator for planning
1) Salary vs dividend balance
Directors often blend salary and dividends. A small salary can support state pension qualifying years and may reduce corporation tax as a deductible cost, while dividends are paid from post-tax profits and taxed personally under dividend tax rates.
2) Pension contributions
Employer pension contributions are usually deductible for corporation tax (subject to rules), so they can reduce company profits while building long-term personal wealth tax-efficiently.
3) Reinvesting profits
Not all profits need to be distributed. Retaining profits in the company can support growth, provide resilience, and defer personal tax points compared with immediate extraction.
Important limitations
- This is an estimate tool, not a filing engine.
- Dividend tax here is simplified and does not fully model total personal income, allowances tapering, or PAYE/NI interactions.
- No VAT, employer NIC, student loan, or payments on account calculations are included.
- No specialist reliefs (like R&D, patent box, creative reliefs) are included.
Frequently asked questions
Is this a corporation tax calculator for all UK businesses?
It is designed for UK limited companies and gives a straightforward estimate. Partnerships and sole traders use different tax systems.
Does it include marginal relief automatically?
Yes. If profits land between lower and upper limits, marginal relief is applied in the result.
Can I use this as my final return figure?
No. Treat it as a planning model. Your final CT600 figure should come from proper accounts and tax adjustments.