This part of GOV.UK is being rebuilt – find out what beta means

HMRC internal manual

Capital Gains Manual

Securities: debts: what is a debt: documentation

There does not need to be any written evidence of a debt, but often the borrower (debtor) will give some form of written acknowledgement of the debt to the lender (creditor). These may vary from simple IOUs, to detailed documents covering points such as the terms of repayment, and rates of interest payable on the amounts owing. You may see these documents described variously as Bills of Exchange; promissory notes; debentures; loan notes; loan stock; or corporate bonds. Although these names may give some indication of the types of debt, they are not, in themselves, important in determining the Capital Gains Tax treatment of the debts.