How to Calculate Corporation Tax

A Limited Company will pay corporation tax according to how much profit is made during one accounting period.

In this guide, I’ll show you how to calculate corporation tax using an easy-to-follow example, along with where you can find more resources on how to reduce your corporation tax bill using allowances, reliefs and other adjustments.

This guide is for Limited Company owners. If you are registered as self-employed you’ll pay income tax and national insurance instead.

What is Corporation Tax?

Corporation tax is a UK tax paid by Limited Companies on their taxable profits. The current UK corporation tax rate is 19%.

What are Taxable Profits?

When you calculate corporation tax you need to use a figure known as taxable profit.

Normally on the profit and loss account, there is a line for profit before tax. In the example below profit before tax is £130,750.

operating profit

When it comes to working out corporation tax, adjustments are made to the profit before tax number for things like:

  • Capital allowances;
  • Previous years trading losses;
  • Associated companies (until 31 March 2015);
  • Depreciation;
  • Disallowable expenses like entertainment.

Corporation tax is based on the figure after all these adjustments are made.

How to Calculate Corporation Tax

Using our example above, let’s suppose the business had the following tax adjustments to make:

  • Entertainment £5,000
  • VAT penalties £1,200
  • Capital allowances for a new laptop £1,400
  • Depreciation £2,500

Taxable Profits would be:

Profit before tax£130,750
Add back:
Entertainment (disallowable business expense)£5,000
Depreciation (disallowable business expense)£2,500
VAT penalties (disallowable business expense)£1,200
Capital allowances£1,400
Taxable profit£138,050
Corporation tax payable (19%)£26,229.50
Corporation Tax Calculation

Corporation tax for an Ltd is generally due for payment 9 months and 1 day after the end of an accounting period, with the tax return needing to be filed with HMRC 12 months after the end of the accounting period

When is Corporation Tax Due for a Limited Company?


About Anita Forrest

Anita Forrest is a Chartered Accountant, spreadsheet geek and money nerd helping financial DIY-ers organise their money so they can hit their goals quicker.