Corporation tax calculator

How this is worked out

In the UK a company with a profit of ￡50,000 or less pays the small profits rate of 19%, and one with a profit of ￡250,000 or more the main rate of 25%. In between it pays the main rate less the marginal relief, 1.5% of what the profit falls short of ￡250,000, so each pound of profit between the two limits is taxed at 26.5%.

In Canada active business income pays the federal small business rate of 9% up to the $500,000 business limit and 15% above it, plus the province's own small business and general rates. Investment income pays 38.67% federal tax plus the provincial general rate. Part of that tax, 30.67% of the income, comes back to the company when it pays non-eligible dividends: 38.33% of each dividend, until that part is used up. In the US a C corporation pays the state's corporate income tax and the federal 21% on the profit less the state tax, which it deducts.

Assumptions and limits

A company on its own, with no associated company sharing its limits, at the rates in force on 1 July 2026 (the financial year from 1 April 2026 in the UK). In Canada: a Canadian-controlled private corporation whose group had no more than $50,000 of investment income the year before, so its business limit is whole, and in Quebec one that does not meet the 5,500 hours test for the provincial small business rate. In the US: a C corporation at the state's 2026 rates, with no city, franchise or gross receipts tax. Losses carried from other years, the UK's rules for augmented profits and close investment-holding companies, and Canada's tax on dividends received are not included.