Corporation tax is payable by all UK limited companies on their taxable profits, which include trading income, investment profits, and capital gains.

Corporation tax liability is calculated on a company's total taxable profits, encompassing income from business activities, investment earnings, and gains from asset disposals. This broad tax base means that businesses must accurately track and report all profit sources to HMRC, and that tax planning requires a holistic view of all income streams, not just core operations.