Glossary term
Interest Rate
An interest rate is the price of money, stated as a percentage of the balance per year. Borrowers pay it to lenders, and savers earn it from banks. The rate alone does not include fees or compounding, so it can understate the true yearly cost of a loan or overstate a simple comparison of savings accounts.
Updated October 17, 2026 · Editorial Team
How Interest Rate works in practice
Lenders and banks quote interest as an annual rate, but they usually apply it in smaller pieces. A loan at 9.00% a year charges 0.75% a month on the outstanding balance. A savings account at the same rate credits a slice of interest each period, which may then compound.
Here is the simplest case: borrow $8,000 at 9.00% and repay it all after one year with no compounding. Interest is $8,000 × 0.09 = $720.00, so you repay $8,720.00. With a monthly amortizing loan the dollar interest would be lower, because the balance shrinks with each payment.
Rates can be fixed, staying the same for the life of the loan or deposit, or variable, moving with a benchmark. Your rate depends on your credit, the loan's term and security, and wider market conditions. A small rate difference matters more on large balances and long terms.
Interest Rate: quick questions
What is the difference between a fixed and a variable rate?
A fixed rate stays the same for the full term. A variable rate is tied to a benchmark and can rise or fall, which changes your payment or earnings.
Why did I get a higher rate than advertised?
Advertised rates usually go to applicants with strong credit and favorable terms. Your score, income, the loan term and any collateral all affect the rate you are offered.
How is an annual rate applied monthly?
Most loans divide the annual rate by 12 and charge that on the current balance each month. Some use a daily rate instead, based on a 365- or 360-day year.
Sources
- Selected Interest Rates – H.15 release — Federal Reserve Board. Accessed October 17, 2026.
- Regulation Z (Truth in Lending), 12 CFR Part 1026 — Consumer Financial Protection Bureau. Accessed October 17, 2026.
We cite primary sources: regulators, central-bank data and federal agencies. Worked examples on this page are our own calculations. See our methodology.
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