Banky team Reviewed editorial answerThe monthly figure is not set by the amount alone. The return on any certificate or deposit is set by three things together: the amount, the term and the payout frequency. Saying 'monthly' fixes the frequency, but the term is still missing, and the term changes which products are available and at what rate.
Hypothetical example per 100 pounds with monthly payout: over 12 months at 18% a year the payout is 1.5 pounds; over 36 months at 20% it is about 1.67 pounds. Same amount, same frequency, two different figures because of the term.
Another point: many certificates are sold as a minimum and its multiples, so if part of your amount is not a multiple, that part is not placed in that certificate and the return is computed only on what is placed. Sometimes the amount itself falls in a band with a different rate.
To find your figure: set the amount, the term and the payout frequency, ask the bank for the return computed on your amount for each product, and check the key-facts statement for the minimum and its multiples and the annual rate for each term and payout.