Yes, your money grows through interest, but the amount depends on the rate your bank offers

Money in a savings account grows when the bank pays you interest — a percentage of your balance that the bank adds to your account on a regular schedule. The bank uses your deposited money to make loans and investments, and shares a portion of what it earns with you as interest. The more money you keep in the account and the higher the interest rate, the more your balance increases over time.

How much your money grows is not automatic or may provide. It depends entirely on the annual percentage yield (APY) the bank advertises for that account. A savings account earning 0.01% APY will grow almost imperceptibly. One earning 4.5% APY will grow noticeably faster. The difference between these two rates means hundreds or thousands of dollars over several years on the same starting balance.

Interest compounds, meaning the bank pays interest on your interest. If you deposit $10,000 at 4% APY and never touch it, after one year you have $10,400. The next year, the bank pays 4% on $10,400, not just the original $10,000. Over decades, this compounding effect becomes substantial — but only if the rate stays competitive and you leave the money untouched.

Key Takeaways

  • Banks pay interest on savings account balances, expressed as an annual percentage yield (APY), and this is the only way your money grows in a savings account.
  • Interest rates vary widely between banks — from under 0.01% at some large national banks to over 4% at online banks — so comparing rates before opening an account matters.
  • Interest compounds regularly (usually daily or monthly), meaning you earn interest on your interest, which accelerates growth over time.
  • The Federal Reserve sets a benchmark rate that influences what banks offer, so rates rise and fall with economic conditions, not because of anything you do.

How banks set the interest rate on your account

Your bank does not decide your interest rate independently. The Federal Reserve sets a benchmark rate (called the federal funds rate) that influences what all banks offer. When the Fed raises its rate, banks typically raise savings account rates. When the Fed lowers its rate, banks lower theirs. This is why savings account rates have climbed since 2022 and may fall again if the Fed cuts rates.

Within that environment, individual banks compete for deposits. Large national banks with many branches often offer lower rates because customers come to them for convenience and brand recognition. Online-only banks, which have lower overhead costs, often offer higher rates to attract depositors who will never walk into a physical location. Credit unions sometimes offer competitive rates to their members. Shopping around for the best rate can mean the difference between 0.01% and 4.5% on the same $10,000 balance.

Banks can also change your rate at any time after you open the account. A rate advertised when you sign up is not locked in for life. Some banks lower rates gradually as the Fed cuts rates; others drop them quickly. Read the terms your bank sends you, because rate changes often arrive by email or mail with little fanfare.

How often interest is added to your account

Banks compound interest on different schedules. Some compound daily, some monthly, and some quarterly. The more frequently interest compounds, the faster your money grows, though the difference is usually small on modest balances. A $10,000 balance earning 4% APY grows to $10,400 in one year whether the bank compounds daily or monthly — the APY already accounts for the compounding frequency.

What matters more is the APY itself. A bank that compounds daily at 0.5% APY will grow your money slower than a bank that compounds monthly at 4% APY. The APY is the standardized number that lets you compare accounts fairly across different banks and compounding schedules.

You can see when interest posts to your account by checking your statement or logging into your online banking portal. Most banks show interest deposits monthly, though the compounding may happen more frequently behind the scenes. If your bank compounds daily but posts monthly, you will see one lump deposit each month that represents all the daily interest earned.

Why some savings accounts grow faster than others

The primary reason is the APY. A high-yield savings account at an online bank earning 4.5% APY will grow your $10,000 to $10,450 in one year. A traditional savings account at a large bank earning 0.01% APY will grow the same $10,000 to $10,001 in one year. Over ten years, that difference compounds into thousands of dollars.

Account type also matters. Money market accounts sometimes offer slightly higher rates than standard savings accounts at the same bank, though they may require a larger minimum balance. Certificates of deposit (CDs) lock your money away for a fixed term (three months to five years) but often pay higher rates than savings accounts because the bank knows it can use your money for that entire period without you withdrawing it.

Your own behavior affects growth too. If you make regular deposits, your balance grows faster because interest compounds on a larger amount. If you withdraw money frequently, you reduce the balance that earns interest. If you move money to a lower-rate account or keep cash outside the bank, that money earns nothing.

The difference between savings accounts and other places to keep money

A savings account is designed to earn interest while keeping your money accessible. You can withdraw funds whenever you need them (though some accounts limit free withdrawals per month). The trade-off is that the interest rate is lower than you might earn elsewhere.

A CD pays a higher rate but locks your money for a set period. If you withdraw before the term ends, you pay a penalty that can wipe out all the interest you earned. CDs make sense if you know you will not need the money for six months, one year, or longer.

A money market account is a hybrid: it earns interest (sometimes higher than a savings account) but limits your withdrawals and may require a larger minimum balance. A regular checking account typically earns little to no interest; it is designed for frequent transactions, not growth.

Keeping money in cash under your mattress or in a non-interest-bearing account means your money does not grow at all. Inflation actually makes it worth less over time, because prices rise while your cash stays the same.

How to compare savings accounts and find the best rate

Start by checking the current APY at several banks. Websites like Bankrate, DepositAccounts, and NerdWallet list rates from many banks side by side, updated regularly. Look at the APY, not just the interest rate — APY includes the effect of compounding and is the true measure of growth.

Check the minimum balance requirement. Some banks require $1 to open; others require $25,000. If you do not meet the minimum, you may not earn the advertised rate or may have to pay a monthly fee that erodes your interest earnings.

Verify that the bank is FDIC-insured (or NCUA-insured if it is a credit union). This means your deposits up to $250,000 are protected if the bank fails. Online banks are just as safe as brick-and-mortar banks as long as they carry this insurance.

Read the fine print about withdrawal limits and fees. Some accounts limit free withdrawals to a certain number per month. Others charge a fee if your balance drops below a minimum. These costs reduce your net interest earnings.

What happens to your interest if rates fall

If the Federal Reserve cuts rates, banks will lower the APY on new deposits and existing accounts. Your money does not disappear, but it grows more slowly. A balance earning 4.5% APY might drop to 3% or lower if the Fed cuts rates significantly.

This is why locking in a high rate matters. If you open a CD at 4.5% for one year, that rate is may provide for the full year even if the Fed cuts rates and savings accounts drop to 2%. Your money continues growing at 4.5% until the CD matures.

For a regular savings account, your rate can change at any time. Some banks lower rates gradually; others do it all at once. You can move your money to a different bank if your current bank's rate becomes uncompetitive, though you will lose any interest that has not yet posted.

Frequently Asked Questions

How much money do I need to start earning interest?

Most banks pay interest on any balance, even $1. However, some accounts require a minimum balance to earn the advertised APY — often $500 to $25,000. If your balance falls below the minimum, you may earn a lower rate or no interest at all. Check your bank's terms before opening an account.

Can I lose money in a savings account?

Your balance cannot go down due to interest rates or market conditions. However, you can lose purchasing power to inflation if your APY is lower than the inflation rate. If inflation is 3% and your savings account earns 1%, your money is effectively worth less each year even though the dollar amount stays the same.

Is it better to keep money in a savings account or a CD?

A CD pays more interest but locks your money away. Use a savings account if you might need the money within a year or two. Use a CD if you know you will not touch the money for a specific period and want to lock in a higher rate. Many people use both: a savings account for emergencies and a CD for money they are saving toward a specific goal.

Do I have to pay taxes on interest I earn?

Yes. Interest earned in a savings account is taxable income. Your bank will send you a 1099-INT form at the end of the year if you earned $10 or more in interest. You report this on your tax return. The amount is usually small unless you have a large balance in a high-rate account.

What if my bank stops offering a competitive rate?

You can move your money to a different bank. Open a new account at a bank with a better rate, then transfer your balance from the old account. There is no penalty for switching banks with a savings account (unlike CDs). Your FDIC insurance follows you to the new bank as long as it is also FDIC-insured.