An interest rate is the percentage of money a bank charges you to borrow, or pays you to save

When you borrow money from a bank—through a loan, credit card, or mortgage—the bank charges you interest. That charge is expressed as a percentage of the amount you borrowed, calculated over a specific time period, usually one year. When you deposit money in a savings account, the bank pays you interest on that deposit. In both cases, the percentage is the interest rate.

The interest rate determines how much extra money changes hands. If you borrow $10,000 at a 5% annual interest rate, you owe $500 in interest over one year (before any payments reduce the balance). If you deposit $10,000 in a savings account at 0.5% annual interest, the bank pays you $50 over one year. The rate itself is just the percentage—the actual dollar amount depends on how much money is involved and how long the money sits.

Key Takeaways

  • Interest rates are percentages that banks charge borrowers or pay savers, calculated as a portion of the total amount of money involved.
  • A higher interest rate on a loan means you pay more money back; a higher rate on savings means you earn more.
  • Banks set rates based on what the Federal Reserve does, what they think will happen to inflation, and how risky they think lending to you is.
  • The same bank may offer different rates to different people, depending on credit history, income, and the type of loan or account.

How banks decide what interest rate to charge you

Banks do not set rates in isolation. The Federal Reserve—the central bank of the United States—sets a target range for the federal funds rate, which is the rate banks charge each other to borrow overnight. When the Fed raises or lowers that rate, banks adjust the rates they offer to customers. If the Fed raises rates, banks typically raise the rates on new loans and lower the rates on savings accounts. If the Fed cuts rates, the opposite usually happens.

Beyond what the Fed does, banks also look at inflation expectations and how much risk they think they are taking. If a bank believes inflation will be high, it may charge higher rates to protect itself from being repaid in money that is worth less. If you have a strong credit history and steady income, the bank sees you as lower risk and may offer you a lower rate. If you have missed payments before or have high debt, the bank sees you as higher risk and may charge you more.

Different types of loans and accounts also carry different rates. A mortgage rate is usually lower than a credit card rate because a house is collateral—if you stop paying, the bank can take it back. A credit card has no collateral, so the bank charges more to cover the risk that you will not pay.

Fixed rates versus variable rates

A fixed interest rate stays the same for the entire life of the loan or account. If you take out a 30-year mortgage at 6%, you pay 6% for all 30 years, even if the Fed raises rates to 8% next year. This makes your payments predictable—you know exactly what you owe each month.

A variable interest rate (also called an adjustable rate) changes over time, usually tied to what the Fed does or to a specific market index. If you have a variable-rate credit card and the Fed raises rates, your card's rate may rise within a billing cycle or two. Variable rates often start lower than fixed rates, which can make them attractive at first, but they carry the risk that your payment will jump if rates rise.

Most mortgages are fixed-rate. Most credit cards are variable-rate. Savings accounts are usually variable, meaning the bank can lower what it pays you whenever it wants.

Why the same bank charges different people different rates

Banks use your credit score as a primary tool to decide your rate. Your credit score is a three-digit number (usually between 300 and 850) that reflects your history of borrowing and repaying money. The higher your score, the lower the rate you will usually receive. Someone with a 750 credit score might get a car loan at 4%, while someone with a 620 score might get the same loan at 8%.

Banks also look at your income, how much debt you already carry, how long you have worked at your current job, and whether you own a home. A person who earns $100,000 a year and has no other debts will usually get a better rate than someone earning $40,000 with existing loans. The bank is assessing the likelihood that you will pay back what you borrow.

The type of collateral also matters. A secured loan (one backed by collateral like a car or house) carries a lower rate than an unsecured loan (like a personal loan or credit card) because the bank has something to take if you do not pay.

How interest rates affect what you actually pay

On a loan, a higher interest rate means you pay more money over time. If you borrow $200,000 for a house at 5% over 30 years, you will pay roughly $186,000 in interest. At 6%, you will pay roughly $215,000 in interest—an extra $29,000 for the same house. Even a 1% difference compounds significantly over decades.

On savings, a higher interest rate means you earn more without doing anything. A savings account at 4% annual interest will earn you twice as much as one at 2%, assuming the same balance. Over five years, $10,000 at 4% grows to about $12,167, while $10,000 at 2% grows to about $11,049. The difference is $1,118 in your favor.

Credit cards show the impact most immediately. If you carry a $5,000 balance on a card charging 18% interest, you owe $900 in interest over one year (if you make no payments). The same balance at 12% costs $600. That $300 difference is money that could go toward paying down the balance instead.

Annual Percentage Rate (APR) versus interest rate

Banks often advertise an Annual Percentage Rate, or APR, rather than just an interest rate. The APR includes the interest rate plus any fees the bank charges (like origination fees on a loan or annual fees on a credit card). The APR is meant to show you the true cost of borrowing in one number.

For example, a loan might have a 5% interest rate but a 1% origination fee. The APR might be 5.8% because it rolls the fee into the yearly cost. When comparing loans or credit cards, the APR is usually more useful than the interest rate alone because it reflects what you will actually pay.

Savings accounts typically show only the interest rate, not an APR, because there are usually no fees involved. Some banks advertise an Annual Percentage Yield, or APY, which includes the effect of compounding—the way interest earned gets added to your balance and then earns interest itself.

What happens when interest rates change

When the Federal Reserve raises interest rates, banks raise the rates they charge on new loans and lower the rates they pay on savings. This makes borrowing more expensive and saving more rewarding. If you have a fixed-rate loan, your payment does not change. If you have a variable-rate loan or credit card, your payment may increase.

When the Fed cuts rates, the opposite happens. Borrowing becomes cheaper, but saving becomes less rewarding. Banks lower the rates on new loans and raise the rates on savings accounts (though they often raise savings rates more slowly than they cut loan rates).

These changes ripple through the economy. When rates rise, people borrow less and save more, which can slow spending and inflation. When rates fall, people borrow more and spend more, which can speed up the economy but also fuel inflation. The Fed uses rate changes as a tool to try to keep inflation stable and unemployment low.

Frequently Asked Questions

What is a good interest rate on a loan?

A good rate depends on the type of loan, current market conditions, and your credit score. Mortgage rates typically range from 3% to 8%, car loans from 3% to 10%, and credit cards from 15% to 25%. Check what the Fed's current rate is and what rates your bank is advertising to see where you stand relative to the market.

Why do banks pay such low interest on savings accounts?

Banks pay low rates on savings because they can borrow money cheaply from the Federal Reserve and from other banks. They lend that money out at much higher rates (mortgages, car loans, credit cards) and keep the difference as profit. When the Fed raises rates, banks eventually raise savings rates too, but the lag can be weeks or months.

Can I negotiate my interest rate with a bank?

You can ask, especially on mortgages, car loans, and credit cards. Banks sometimes offer better rates to customers who have been with them for years, who have multiple accounts, or who have strong credit. The worst they can say is no. For credit cards, you can also call and ask for a lower rate based on your payment history.

What does it mean if a rate is compounded daily?

Compounding means interest is calculated on your balance, then added to it, and then the next interest calculation includes that added amount. Daily compounding means this happens every day. More frequent compounding means you earn slightly more on savings or owe slightly more on loans, because interest earns interest. Most savings accounts compound daily; most loans compound monthly.

How do I find the current interest rate environment?

The Federal Reserve publishes its target rate on its website (federalreserve.gov). Major news outlets report when the Fed changes rates. Your bank's website shows the rates it is currently offering on savings accounts, CDs, mortgages, and credit cards. Comparing rates across banks takes 15 minutes and can save you thousands of dollars.