What each number includes
The interest rate, sometimes called the note rate, is what sets your monthly payment. It is charged only on the principal. The APR takes that rate and adds most of the upfront costs of getting the loan, such as origination fees, points, and certain closing costs, then expresses the whole thing as a single yearly rate. Because it includes fees, the APR is almost always higher than the interest rate, and the gap tells you how expensive the fees are.
A worked example
Two loans can share the same rate but have very different APRs if one charges heavy fees.
- Note interest rate6.5 percent
- Monthly payment (rate only)$1,580
- Upfront fees$6,000
- APR including those fees≈ 6.74 percent
The payment is set by the 6.5 percent rate, but the loan really costs about 6.74 percent a year once the fees are counted. A competing loan advertised at 6.4 percent with 12,000 dollars in fees could easily have a higher APR, and cost you more.
Which number to use, and its limits
Compare loans of the same type and term by APR, because it captures fees the sticker rate hides. But APR has a blind spot: it spreads the fees over the full loan term. If you sell or refinance early, you never reach the point where a low rate with high fees pays off, so a loan with lower fees and a slightly higher rate can be the better deal. Compare APR first, then sanity check it against how long you actually expect to keep the loan.
Frequently asked questions
Why is APR higher than the interest rate?
Which should I use to compare loans?
Does a lower APR always mean a cheaper loan?
Is APR the same on credit cards?
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More guides
Plain-English explainers for the money questions behind each calculator.