Why is the upfront rate lower than the monthly-payout rate, and how do I compare them?

Because the payout method is part of the pricing. With an upfront return the bank pays the whole return at the start; with monthly payout it pays in instalments over the term; and each method has its own rate in the product's grid. So comparing the upfront rate with the monthly rate as headlines does not tell you which pays more money, or when.

• There is a second reason: the upfront figure may be computed per year or for the whole term, which matters a great deal for terms longer than a year.

Hypothetical example per 100 pounds in a 1-year deposit: monthly payout at a hypothetical 20% gives about 1.67 pounds a month, 20 pounds over the year. An upfront payout at a hypothetical 17.5% for the year gives 17.5 pounds once, on day one. The two differ in amount and in timing, and the choice depends on when you need the money.

The comparison that means something: same amount, same term, and the money actually paid under each payout method with its dates. Ask the bank for the amount computed on your sum for each payout method, and confirm the basis of the upfront rate in the key-facts statement.