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TREGGENA ADVICE - CASTLE EDEN & UK-WIDE
Company profits.
A clearer tax estimate.
Estimate Corporation Tax for a full 12-month accounting period, with the small-profits rate, main rate and Marginal Relief where applicable.
YOUR FIGURES
Start with the numbers.
Full 12-month accounting period from 1 April 2023 onwards · UK-resident trading company eligible for the small-profits/Marginal Relief rules. Excludes shorter periods, close investment-holding companies, ring-fence profits and special regimes. Enter taxable profits after adjustments and reliefs, not turnover.
UNDERSTAND THE ESTIMATE
Three things to keep in mind.
Use taxable profits
Accounting profit often needs adjustments for tax. Enter the figure after the relevant tax adjustments and reliefs.
Check the profit limits
The usual £50,000 and £250,000 limits are divided by the total number of associated companies, including this company.
Allow for the wider calculation
Relevant exempt distributions affect augmented profits and Marginal Relief. Short periods, special company types and other reliefs need a separate calculation.
BEFORE YOU RELY ON THE RESULT
A little more detail.
Information checked 2 October 2026. Corporation Tax Marginal Relief · HMRC calculation formula