APR vs interest rate: which number tells you the real cost

The interest rate is the yearly cost of the money you borrow. The APR is a broader yearly rate that also counts finance charges such as points and loan fees. On a loan with an upfront fee, APR is higher than the rate. For example, a $10,000 36-month loan at 10% with a $500 origination fee has an APR of 13.56%, so it is more expensive than a fee-free loan at 11.5%.

What the law says each number is

The CFPB defines the interest rate as the yearly cost of borrowing, without fees. The APR is a broader measure that adds points, broker fees and other charges you pay to get the loan.

The rule behind it is Regulation Z. 12 CFR 1026.4 defines the finance charge as the cost of credit in dollars, including interest, points, loan fees, service and transaction charges, and credit insurance premiums charged as a condition of the loan. For closed-end loans such as auto loans, personal loans and mortgages, 12 CFR 1026.22 defines the APR as a yearly rate that relates the amount and timing of value you receive to the amount and timing of payments you make. A disclosed APR counts as accurate if it is within 1/8 of one percentage point of the true figure (1/4 point for irregular transactions).

Worked example: a fee changes which offer is cheaper

Take two $10,000 loans over 36 months. Offer A has a 10% rate and a 5% origination fee deducted from the proceeds. Offer B has an 11.5% rate and no fee. Payments are computed in Python as a standard amortizing loan, and the APR is the rate that makes the payments worth exactly the cash received.

Offer A has the lower rate and the lower payment, and costs $244.83 more. The $500 fee is paid back on money you never received, since you owe interest on $10,000 but get $9,500.

The same fee costs more on a shorter loan

The $500 fee is fixed, so spreading it over fewer months raises the APR. For the same 10% loan with a 5% fee:

At 60 months Offer A still has the higher APR (12.24% against 11.5%) and costs $52.67 more. Its total cost of borrowing is $3,248.23 against $3,195.56.

When APR misleads: paying the loan off early

APR assumes you keep the loan for the full term. Suppose you take Offer A for 60 months and repay the remaining balance after 12 payments. The balance then is $8,377.32. Treating the $9,500 received, 12 payments of $212.47 and that payoff as the cash flows, your effective yearly cost is about 15.86%, not the 12.24% disclosed. A fee-free loan costs its rate whenever you repay. If you expect to pay early, prefer the lower fee, and see pay off a loan early or invest.

Where each number appears

• Mortgages. On the Loan Estimate, the CFPB says the interest rate is on page 1 under "Loan Terms" and the APR is on page 3 under "Comparisons."
• Credit cards. Under 12 CFR 1026.14, when interest through periodic rates is the only finance charge, the APR is the periodic rate multiplied by the number of periods in a year. A daily rate of 0.06068% times 365 gives 22.15%. It does not include compounding, so the effective yearly cost is higher. See how credit card interest works.
• Personal and auto loans. The APR is on the loan disclosure, calculated as in the example above.

Comparison cautions the CFPB gives

• For adjustable-rate mortgages, the APR does not reflect the loan's maximum interest rate.
• Be careful comparing fixed-rate APRs with adjustable-rate APRs.
• Do not compare a closed-end loan's APR, which includes fees, with a home equity line of credit's APR, which does not.

Also compare over the same term. A 60-month loan has a lower payment than a 36-month loan and a higher total cost. Use the loan payment calculator to total each offer, and see is a balance transfer worth it for how fees change a 0% offer.

Questions to ask a lender

1. What is the APR, and is the rate fixed or variable?
2. What is the origination fee, and is it deducted from the proceeds or added to the balance?
3. Is there a prepayment penalty?
4. What is the total of payments?
5. Does the quoted rate depend on autopay or a specific term?

Frequently asked questions

Sources

1. What is the difference between a mortgage interest rate and an APR?, Consumer Financial Protection Bureau. Checked October 2026.
2. 12 CFR 1026.4, Finance charge, Legal Information Institute, Cornell Law School. Checked October 2026.
3. 12 CFR 1026.22, Determination of annual percentage rate, Legal Information Institute, Cornell Law School. Checked October 2026.
4. 12 CFR 1026.14, Determination of annual percentage rate, Legal Information Institute, Cornell Law School. Checked October 2026.