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.
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.