So, against my advice my mother invested in some of those Ulster Bank Combination Accounts several years ago. A proportion (in this case 20%) was 'deposited' in a high interest account (capital and interest of 10% paid after 2 years) and the balance was 'invested' with a view to 80% of the increase in a basket of shares paid out as a return at the end of the period. In this case, the return was of the order of 15% over 4 years. Now that the balance of her funds have been returned, I'm trying to ascertain the tax treatment of the two parts. As I would read it, DIRT should be taken from the interest paid after 2 years, but what is the classification of the second gain. If this is a capital gain, she'd be covered by the small annual allowance. If it's interest, there would be a further DIRT liability. Any had to deal with these products (and their taxation) before?