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HMRC internal manual

Business Income Manual

Measuring the profits (general rules): statutory rules: introduction and layout of guidance: contents

Historically, the rules which determine how the profits of a trade are measured for tax purposes have been based largely on principles established by the Courts. In recent years, however, basic statutory rules have been established to provide a framework for the computation of profits. The statute does not attempt to provide a comprehensive set of rules to cover every situation and is derived from the pre-existing case law principles. The guidance on the rules is laid out as follows.