The Financial Regulator's Consumer Protection Code (Chapter 3: Banking Products & Services) specifies the following requirements with respect to changes in interest rates:
A credit institution must ensure that when it announces a change in interest rates, the notification states clearly the date from which the changes will apply.
Where a credit institution changes the interest rate on accounts, it must update the information on information services, including telephone helplines and websites as soon as the change comes into effect.
In addition, the Deputy may wish to note that changes to, and notification of, interest rates on loan accounts are governed principally by the loan agreement between the lender and the borrower.