APR vs Interest Rate: What Is the Difference?
Why a loan's APR and its interest rate are not the same number, and which one actually tells you the true cost of borrowing.
Every loan advertisement shows an interest rate, and most show an APR too — and they're almost never the same number. Knowing what separates them is the difference between comparing loans accurately and being misled by whichever number happens to look better.
What the Interest Rate Tells You
The interest rate is what your monthly payment is based on. It's the rate applied to your outstanding balance to calculate the interest portion of each payment. If two loans have the same amount, term, and interest rate, they'll have the same monthly payment — regardless of any fees attached to either one.
What APR Adds
Annual Percentage Rate folds in certain upfront fees — commonly an origination fee — and expresses the total cost of borrowing as an equivalent annual rate. Because you pay interest on the full loan amount but don't receive the full amount in cash when a fee is deducted upfront, the true cost of borrowing is higher than the interest rate alone suggests. APR is the number designed to reflect that.
A Concrete Example
Consider a $10,000 loan at 8% interest over 3 years with no fee: the interest rate and the APR are effectively the same. Now add a $500 origination fee deducted from the loan proceeds. You still owe $10,000 and still make the same payment calculated on $10,000 at 8% — but you only received $9,500. Measured against what you actually got, the true annual cost is higher than 8%, and that higher figure is the APR.
Why This Matters When Comparing Loans
A loan with a lower interest rate but a large origination fee can end up more expensive than a loan with a slightly higher rate and no fee — especially over a shorter term, where the fee makes up a bigger share of the total cost. Comparing by interest rate alone can lead to the wrong choice; comparing by APR accounts for the fee automatically.
Where This Doesn't Apply the Same Way
Credit cards quote APR too, but typically without an origination fee baked in, so the "interest rate vs. APR" gap described here is mainly relevant to instalment loans like mortgages, auto loans, and personal loans.
Use the loan calculator to see the exact gap between a loan's stated rate and its effective APR once you enter an origination fee, or the mortgage calculator for the mortgage-specific version of this same math.