The TAE a bank publishes for a loan or deposit may also include fees and costs; this conversion is the purely financial part of the interest rate.

Formula: TAE = (1 + TIN/k)^k − 1, with k compounding periods per year.

Educational tool based on the financial equivalence of rates (Banco de España, Circular 5/2012). A product's regulated TAE may include fees: always compare the official TAE of the offer.