What's included
Any interest received on investments, for example on a bond, term deposit or savings accounts.
Interest you charge to your clients for not paying you on time.
*Please note, this category does not appear for sole traders. For sole traders the interest gained is treated and categorised as Personal, as it's not taxable for the business (it is instead treated as interest income for the individual).
What's not included
Loan interest received, if the loan was made as an integral part of your normal trade (do confirm with your accountant).
Mark ups on your invoices shouldn't be recorded here either.