What is the 'Annual Equivalent Rate  AER'
The annual equivalent rate (AER) is interest that is calculated under the assumption that any interest paid is combined with the original balance and the next interest payment will be based on the slightly higher account balance. Overall, this means that interest can be compounded several times in a year depending on the number of times that interest payments are made.
In the United Kingdom, the amount of interest received from savings accounts is listed in AER form.
Calculated as:
Where:
n = number of times a year that interest is paid
r = gross interest rate
BREAKING DOWN 'Annual Equivalent Rate  AER'
For example, a savings account with a quoted interest rate of 10% that pays interest quarterly would have an annual equivalent rate of 10.38%. Investors should be aware that the annual equivalent rate will typically be higher than the actual annual rate calculated without compounding.

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