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HMRC internal manual

Business Income Manual

Receipts: general: if excluded may still be liable

Receipts which are not trading receipts of the business may, if of a revenue nature, constitute receipts of a separate business or be liable to tax as income of a different category. If the receipt is excluded because it is of a capital nature, or otherwise if it arises out of an asset or rights of some description, the possibility that a chargeable gain arises should be considered.