APR in the US and Europe: the same name, different math

The annual percentage rate, or APR, is the number a lender must show you before you sign. It looks like one universal figure, but the United States and the European Union define it differently, and comparing the two as if they were the same can mislead you by a fraction of a point that is worth thousands over a mortgage. This guide explains each definition, shows the difference on a real example and says how to compare offers. The rules it cites are the American Regulation Z, the European consumer credit directives and, for Spain, the national name for the APR.

What the APR is for

Two loans with the same interest rate can cost very different amounts once fees are added. The APR exists to put the cost of credit in one yearly figure that includes the interest and certain charges, so that offers can be compared. The catch is in two words: which charges, and how the yearly figure is built.

The United States: a nominal annual rate

Under Regulation Z, the American implementation of the Truth in Lending Act, the APR is expressed as a yearly rate. The method is in Appendix J (opens in a new tab) to the regulation, which says the APR is determined by multiplying the rate per period by the number of periods in a year. For a loan paid monthly, that is the monthly rate times twelve. It is a nominal rate: it does not compound. The charges that enter the calculation are the finance charges, which include the interest and fees the lender imposes as a condition of the loan.

The European Union: an annual rate that matches present values

In the European Union the APR comes from an equation that equates, on an annual basis, the present value of the amounts drawn with the present value of the repayments and charges, with every time measured in years and fractions of a year. The 2008 consumer credit directive is repealed with effect from 20 November 2026 and replaced by Directive (EU) 2023/2225 (opens in a new tab), which keeps the same idea in its annex. Home loans fall under the Mortgage Credit Directive, 2014/17/EU, with the same formula, and the official English name of the rate is the annual percentage rate of charge (APRC). Spain calls the APR the TAE, the annual equivalent rate, and the Banco de España (opens in a new tab) has calculators for it. Because each payment is discounted by the time that has passed, the result is an effective annual rate: the monthly rate is compounded over the year.

Brazil's total effective cost, the CET, is built the same way, as the rate that makes the cash flow of the loan add up to zero, so it should be read next to the European APR and not next to the American one.

An example with numbers

A loan of US$ 300,000.00 over 30 years, at a 6.50% a year rate with monthly payments, first with no fees and then with a fee of US$ 3,000.00 paid at closing and deducted from the amount received:

The same loan reads 6.50% or 6.70% depending on the convention, and the fee adds about a tenth of a point to either. Neither figure is wrong: they answer in different units. To turn an American-style APR into an effective rate, compound the monthly rate: (1 + APR ÷ 12)^12 − 1, which takes 6.50% to 6.70%.

How to compare offers across systems

• Use one convention. Convert before comparing, or you will be comparing 6.50% with 6.70% for the very same loan.
• Ask which charges are inside. An APR is only as complete as the list of charges it counts, so check what the lender included.
• Look at the payment and the total as well. The APR tells you the rate, and the payment and the total tell you whether you can afford it and what it adds up to.
• Remember variable rates. For a loan whose rate changes, the APR typically assumes the rate stays where it started, so it does not forecast what you will pay.

How to see it in the simulation

In the simulation, choose the country, enter the loan with the rate as it was quoted (nominal per year for an American quote) and add the fees under the advanced options. The page shows the effective annual cost including the charges, which is the figure to put beside a European APR. For the difference between the two kinds of rate, read nominal and effective rates, and for what the cost includes, the guide on the total effective cost.