September 4th, 2026 9:43 AM by Sam Kader NMLS# 130505
When comparing mortgage loans, you will usually see two percentages: the mortgage interest rate and the annual percentage rate, or APR. Although these figures are related, they measure different aspects of a home loan.
Understanding the difference between an interest rate and an APR can help you evaluate mortgage offers more carefully. Neither number should be considered by itself. Loan fees, monthly payments, loan structure, rate-lock period and the length of time you expect to keep the mortgage may all affect which option is appropriate for you.
The interest rate is the cost charged for borrowing the principal loan amount, expressed as an annual percentage. It is used to calculate the principal-and-interest portion of your monthly mortgage payment.
The interest rate generally does not include discount points, mortgage broker compensation, lender fees or other charges associated with obtaining the loan. Property taxes, homeowners insurance, mortgage insurance and homeowners association dues are also separate from the interest rate.
All other factors being equal, a lower interest rate generally results in a lower principal-and-interest payment. However, obtaining a lower rate may require paying discount points or accepting different loan terms. That is one reason it is important to compare both the rate and the total estimated costs.
The annual percentage rate is a broader measure of the cost of borrowing. In addition to the interest rate, the APR generally incorporates certain finance charges connected with obtaining the mortgage.
Depending on the transaction, the APR calculation may include:
Because the APR includes the interest rate and certain additional costs, it is often higher than the note rate. However, that will not be true in every situation, particularly with some adjustable-rate mortgages.
APR can help you compare the estimated cost of similar mortgage offers. For example, one loan may have a lower interest rate but require substantial discount points or finance charges. Another may have a slightly higher rate with lower upfront costs.
Comparing the APRs may help identify how these costs affect the overall price of each loan under the assumptions used in the calculation. For the comparison to be meaningful, the loans should have similar terms, loan amounts, lock periods and repayment structures.
The lowest advertised interest rate is not necessarily the least expensive loan. A lower rate may be accompanied by higher discount points or other finance charges. Review the interest rate, APR, lender credits, discount points and total closing costs together.
APR is a helpful comparison tool, but it does not provide a complete picture of a mortgage. APR alone may not clearly show:
Balloon payments, prepayment penalties and adjustable-rate features are addressed separately in the loan disclosures. Review the complete Loan Estimate rather than relying exclusively on the APR.
Additional care is needed when evaluating the APR on an adjustable-rate mortgage, or ARM. An ARM may have an initial rate that remains unchanged for a specified period and then adjusts according to the loan’s index, margin and rate caps.
The APR is calculated using assumptions required by federal rules, but it does not reflect the maximum interest rate or payment the loan could eventually reach. The interest rate, APR and monthly payment may increase after consummation, depending on the loan terms and future movement of the applicable index.
Use caution when comparing an ARM APR with a fixed-rate mortgage APR or when comparing ARMs with different fixed periods, indexes, margins or adjustment schedules.
APR comparisons are generally most useful when the loans have similar repayment terms. The same upfront finance charges can have a greater effect on the APR of a shorter-term loan because those costs are spread over fewer years.
When comparing a 15-year mortgage with a 30-year mortgage, consider the monthly payment, total projected interest, upfront costs and how long you expect to retain the loan. A shorter loan term may reduce total interest but generally requires a higher monthly payment.
If you receive an official Loan Estimate:
You can learn more through the Consumer Financial Protection Bureau’s explanation of mortgage interest rates and APRs.
The mortgage interest rate helps determine your principal-and-interest payment. The APR provides a broader estimate of borrowing costs by incorporating the interest rate and certain finance charges.
For a meaningful mortgage comparison, review the interest rate, APR, monthly payment, discount points, lender credits, closing costs, loan term, rate-lock period and adjustable-rate features. The most appropriate mortgage will depend on your qualifications, financial circumstances, property, loan program and long-term plans.