Tax calculator

Corporation Tax Calculator

Estimate Corporation Tax for a standard company in financial year 2026.

  • Tax year shown with the calculator
  • Assumptions explained
  • Source-linked methodology

Financial year 1 April 2026 to 31 March 2027

Estimate Corporation Tax for a standard company

Use taxable total profits and augmented profits to estimate the small profits rate, marginal relief or main rate.

Use the taxable total profits for the accounting period after relevant deductions, not turnover or accounting profit.

Enter distributions included in augmented profits. Enter £0 if none or if an adviser has confirmed none are included.

Enter 365 for a full year. This version supports periods wholly within 1 April 2026 to 31 March 2027.

Do not count this company. HMRC divides the thresholds by this company plus every associated company.

Does the company or accounting period need special treatment?

Choose yes for a non-UK resident company, close investment-holding company, ring-fence profits, unassessed transfer-pricing profits, unit trust or open-ended investment company, a period outside or straddling this financial year, or uncertainty about associated companies or distributions.

Your figures are used only for this calculation. They are not added to a lead record or analytics event.

What this estimate includes and excludes

It applies the financial-year 2026 non-ring-fence rates and HMRC marginal-relief formula to the figures entered. It adjusts the thresholds for period length and associated companies.

It does not calculate taxable profits, losses, capital allowances, group relief, R&D or other credits, Patent Box, double-tax relief, quarterly instalments, interest, filing obligations or payment deadlines.

How to understand your result

Your result is an estimate for the tax year shown on the calculator. The breakdown lists each step, the rates and thresholds used, and the date the figures were last checked against GOV.UK. Amounts are rounded the way HMRC rounds them where a rule exists.

Each calculator lists what it leaves out, such as other income, reliefs or special cases, so read the assumptions before you rely on the figure. For your own position, check your HMRC online account or speak to a qualified professional.