What interest rates actually are

An interest rate is the percentage of your money that a bank pays you (or charges you) over time. When you put money in a savings account, the bank pays you interest — a small amount extra — for letting them use your money. When you borrow money through a loan or credit card, you pay the bank interest for the privilege of borrowing.

The rate is expressed as a percentage per year. If a savings account offers 4.5% annual interest and you deposit $1,000, the bank will pay you roughly $45 over twelve months (though the exact amount depends on how often interest compounds, which we'll cover below). The higher the rate, the more money you earn on savings or the more you pay on debt.

Banks set their own rates within limits set by the Federal Reserve. The Fed doesn't dictate exact rates, but it sets a target range that influences what banks charge and pay. When the Fed raises its target, banks typically raise what they charge borrowers and what they pay savers. When it lowers the target, the opposite usually happens.

Key Takeaways

  • Interest rates are percentages that determine how much extra money you earn in savings or pay on borrowed money over a year.
  • Banks compound interest — meaning they calculate interest on your interest — at different intervals (daily, monthly, or quarterly), which affects how much you actually earn.
  • The Federal Reserve influences all bank rates by setting a target range, but each bank chooses its own exact rate based on competition and risk.
  • Savings account rates, money market rates, and CD rates all vary by bank and by how long you lock your money away.
  • Loan and credit card rates depend on the type of borrowing, your credit history, and current Fed policy.

How compounding changes what you actually earn

The stated interest rate is only half the story. What matters more is how often the bank compounds your interest — meaning how often it calculates interest on the interest you've already earned, then adds that to your account.

If a bank compounds daily, it divides the annual rate by 365, calculates interest on your balance each day, and adds it back. If it compounds monthly, it does this twelve times a year. If it compounds quarterly, four times. The more frequently compounding happens, the more you earn, even at the same stated rate.

Banks are required to disclose the Annual Percentage Yield (APY), which is the actual rate you'll earn after compounding is factored in. The APY is always equal to or higher than the stated interest rate. When you're comparing savings accounts, compare APY to APY, not the stated rate — that's the real number.

Why rates differ between account types

Different accounts offer different rates because banks face different risks and costs with each type. A regular checking account typically earns little to no interest because the bank can access your money instantly and faces no penalty if you withdraw it tomorrow. A savings account earns more because you're expected to leave money there longer. A Certificate of Deposit (CD) — where you agree to lock your money away for a set period like six months or five years — earns the most, because the bank knows exactly how long it can use your money.

Money market accounts sit in the middle. They earn more than savings accounts but less than CDs, and they let you write checks or make withdrawals, though usually with limits.

Within each type, rates vary by bank. A large national bank might offer 0.01% on savings while an online bank offers 4.5% on the same account type. The difference reflects competition: online banks have lower overhead costs, so they can afford to pay more. Local banks may offer less competitive rates but provide in-person service or relationship benefits.

How loan and credit card rates work differently

When you borrow money, you pay interest instead of earning it. A loan rate — for a car, home, or personal loan — is usually fixed, meaning it stays the same for the entire loan term. A credit card rate is usually variable, meaning it can change when the Fed changes its target range.

Your personal credit history heavily influences the rate you're offered. Someone with a credit score of 750 might get a car loan at 5%, while someone with a score of 620 might be offered 9% for the same loan. The bank sees lower-credit borrowers as riskier, so it charges more to offset the chance of default.

Loan rates also depend on the type of borrowing. A mortgage (home loan) typically has the lowest rate because the house itself serves as collateral — if you don't pay, the bank can take it. A personal loan, which is unsecured, carries a higher rate. A credit card, which is also unsecured and short-term, usually carries the highest rate of all.

What moves interest rates up and down

The Federal Reserve meets eight times a year to set its target interest rate range. When inflation is high (meaning prices are rising fast), the Fed typically raises its target to cool down the economy and reduce inflation. When the economy is weak or unemployment is high, the Fed typically lowers its target to encourage borrowing and spending.

Banks don't move instantly. When the Fed raises its target, savings rates usually rise within weeks, but loan rates may take longer. When the Fed cuts rates, banks may lower loan rates quickly but hold savings rates steady longer — they're less eager to pay you more when they're earning less.

Economic conditions also matter. During recessions, even if the Fed hasn't moved, banks may lower rates to attract borrowers. During booms, they may raise rates because demand for loans is high and they can afford to be selective.

The difference between fixed and variable rates

A fixed rate stays the same for the entire term of the loan or CD. If you lock in a 5% mortgage rate for thirty years, you pay 5% for all thirty years, regardless of what happens to the Fed's target. This protects you from rate increases but means you don't benefit if rates fall.

A variable rate changes periodically — usually once a year or when the Fed moves. Credit cards almost always use variable rates. Some adjustable-rate mortgages (ARMs) start with a fixed rate for a few years, then switch to variable. Variable rates are riskier because your payment can jump, but they often start lower than fixed rates.

When choosing between fixed and variable, consider how long you'll keep the account or loan. If you're taking out a five-year CD, a fixed rate makes sense — you know exactly what you'll earn. If you're getting a credit card you'll use for years, a variable rate is standard and you should expect it to move with the Fed.

How to find the current rates offered by banks

Banks publish their rates on their websites, usually in a section labeled "Rates" or "Current Rates." You'll see rates for checking, savings, money market, and CDs at different terms (3-month, 6-month, 1-year, 5-year, etc.). For loans, you typically have to request a quote because rates depend on your credit and the specific loan details.

Comparison sites like Bankrate, DepositAccounts, and NerdWallet aggregate rates from many banks so you can see what's available in your region or nationwide. These sites update frequently but may lag by a day or two, so always check the bank's own website before opening an account.

When you see a rate advertised, check whether it's the stated rate or the APY. For savings, always use APY. For loans, the bank is required to show you the Annual Percentage Rate (APR), which includes fees and is the true cost of borrowing.

Frequently Asked Questions

Why does my savings account earn almost nothing when the Fed rate is high?

Large national banks often lag behind in raising savings rates because they attract deposits through other means — branch locations, brand recognition, or bundled services. Online banks and credit unions compete primarily on rate, so they raise savings rates faster. If your bank isn't moving, you may earn more by switching to an online bank.

If I lock money in a CD at 5%, what happens if rates drop to 2%?

You keep earning 5% for the entire CD term — that's the point of locking in a fixed rate. You're protected from rate drops. The tradeoff is that if rates rise to 7%, you're stuck at 5%. You can withdraw early, but most CDs charge a penalty (usually a few months of interest).

Does my credit score affect the interest rate on a savings account?

No. Savings account rates are the same for everyone at a given bank, regardless of credit score. Credit score matters only for borrowing — loans, credit cards, and lines of credit. Banks use credit scores to assess the risk that you won't repay borrowed money.

What's the difference between APR and APY?

APY (Annual Percentage Yield) is used for savings and shows what you actually earn after compounding. APR (Annual Percentage Rate) is used for borrowing and includes fees, showing the true cost of the loan. Always compare APY to APY for savings and APR to APR for loans.

Can a bank change my interest rate on a savings account whenever it wants?

Yes. Savings account rates are not locked in — they're variable by nature. Banks can raise or lower them at any time, though they usually give notice. Loan rates depend on the type: fixed-rate loans are locked in, but variable-rate loans (like some credit cards or ARMs) can change according to their terms.