An endowment mortgage is a financial product offered mainly in the United Kingdom. It consists of an interest-only loan secured on a mortgage combined with an investment in the stock market. The customer pays the interest on the capital, thus saving money with respect to an ordinary repayment loan; the balance is invested in the endowment fund. In the stock market boom of the 1980s and 1990s it seemed plausible that at the end of the loan term, the investment would pay off the capital and leave a surplus for the customer to spend.