The basics: interest is how banks pay you to save

Your money grows in a savings account through interest — a percentage of your balance that the bank adds to your account regularly. The bank pays you interest because they use your deposited money to lend to other customers. The amount you earn depends on three things: how much you have saved, what interest rate the bank offers, and how long the money sits in the account.

Interest is usually paid monthly or daily, though the timing varies by bank. Some banks add it to your account on the first of each month; others calculate it daily but only deposit it once a month or once a quarter. The difference matters more the longer your money stays there, but for most people starting out, the timing is less important than the rate itself.

Key Takeaways

  • Interest rates on savings accounts vary widely between banks — from nearly zero at some large national banks to 4% or higher at online banks, so comparing rates before opening an account can double or triple what you earn.
  • Your money grows faster with compound interest, which means you earn interest on the interest you already earned, but this effect is small in the first year and grows over time.
  • A savings account with a $1,000 balance at 0.01% interest earns about $0.10 per year, while the same $1,000 at 4.5% interest earns about $45 per year — the difference is entirely the rate the bank offers.
  • The bank is required to tell you the interest rate before you open an account, usually listed as APY (Annual Percentage Yield), which already includes the effect of compound interest.
  • Money in a savings account grows slowly compared to other investments, but it is safe, accessible, and earns something rather than sitting in a checking account that pays no interest.

Why interest rates differ so much between banks

Large national banks often offer very low interest rates — sometimes 0.01% or less — while online banks and credit unions often offer rates several times higher. This difference exists because online banks have lower costs (no physical branches to maintain) and compete harder for deposits. A national bank with thousands of branches can afford to pay less interest because customers come for the convenience; an online bank must offer better rates to attract customers.

The Federal Reserve sets a target interest rate that influences what all banks offer, but each bank decides its own rate within that environment. When the Federal Reserve raises its target rate, banks usually raise savings account rates within weeks or months. When it lowers the target rate, banks lower savings rates too — sometimes quickly, sometimes slowly. This means the rate you see today may not be the rate you see in six months.

How to calculate what you will earn

The bank will tell you the interest rate as APY (Annual Percentage Yield). This is the percentage of your balance you will earn in one year, and it already includes the effect of compound interest. To estimate your earnings, multiply your balance by the APY as a decimal.

For example: if you have $2,000 in an account paying 4.5% APY, you multiply $2,000 × 0.045 = $90. You would earn about $90 in one year. If you leave it there for two years without adding or withdrawing money, the second year you earn interest on $2,090 (your original $2,000 plus the $90 from year one), so you earn slightly more than $90 in year two — about $94. This is compound interest at work, but the difference is small in the early years.

If you want to know what you will earn in a specific number of months, divide the annual amount by 12. Using the same example: $90 ÷ 12 = $7.50 per month. This is approximate because compound interest means each month is slightly different, but it is close enough for planning.

The difference between APY and APR

You may see both APY and APR mentioned. APY (Annual Percentage Yield) is what you use for savings accounts — it shows what you will earn. APR (Annual Percentage Rate) is what you use for loans and credit cards — it shows what you will pay. For a savings account, always look at the APY, not the APR.

APY includes the effect of compound interest, so it is always slightly higher than the base interest rate. APR does not include compounding in the same way. This is why the bank must show you APY for savings accounts — it is the honest number that tells you what you actually earn.

Why your money grows slowly in a savings account

Even at a good interest rate like 4.5%, a $1,000 balance earns only $45 per year. This is slow compared to other investments like stocks, which historically return around 7% to 10% per year on average over long periods. However, a savings account is safe — the bank cannot lose your money through bad investments, and your deposits are insured by the FDIC up to $250,000 per account.

A savings account is meant for money you need to reach within a few months or a year or two — an emergency fund, a down payment you are saving for, or money you are setting aside for a known expense. If you have money you will not need for five or ten years, other investments may grow it faster, but those come with risk. A savings account trades growth for safety and access.

How to find the highest interest rate available

Interest rates change frequently, so the rate you see today may not be the best rate available next month. Before opening an account, check the current rates at several banks. Online banks, credit unions, and some regional banks usually offer higher rates than large national chains. Websites that track savings rates can show you which banks are currently offering the highest APY, though you should verify the rate on the bank's own website before opening an account.

Once you open an account, the bank will tell you if the rate changes. Rates can go down without your permission, but you can move your money to a different bank if a better rate appears elsewhere. There is no penalty for closing a savings account and moving your balance to another bank — you are not locked in. Some people move their savings every year or two to chase the highest available rate, though the difference in earnings from moving once versus staying put is usually modest.

What happens if you withdraw money before earning a full year of interest

Interest accrues (builds up) daily or monthly depending on the bank, so if you withdraw money partway through the year, you still earn interest on the balance you held. If you had $2,000 for six months and then withdrew it, you would earn about half of the annual interest — roughly $45 per year becomes $22.50 for six months. You do not lose the interest you already earned; you straightforward earn less because you held less money for less time.

Some savings accounts have restrictions on how many times you can withdraw per month without a fee, though these rules have become less common. Check your account terms before opening to see if withdrawal limits explore. Most banks allow you to move money between your savings account and your checking account as often as you want without penalty.

Frequently Asked Questions

Does the interest rate ever go down after I open an account?

Yes. Banks lower savings rates when the Federal Reserve lowers its target rate, which happens during economic slowdowns. You will receive notice before the rate changes, and you can move your money to a different bank if the new rate is too low. There is no penalty for closing an account.

What is the difference between a savings account and a money market account?

A money market account usually offers a slightly higher interest rate than a regular savings account, but it may require a larger minimum balance and limit how many times you can withdraw per month. For most people starting out, a regular savings account is simpler. Both are insured by the FDIC up to $250,000.

Can I earn more interest by moving my money to a different bank?

Yes, if another bank is offering a higher rate. You can close your account and move your balance without penalty. Some people move their savings every year or two to take advantage of higher rates, though the extra earnings are usually modest — moving $5,000 from a 0.5% account to a 4.5% account gains you about $200 per year.

What if I add money to my savings account throughout the year?

You earn interest on each deposit from the day it arrives. If you deposit $100 on the first of each month, the first deposit earns interest for the full year, the second deposit earns interest for eleven months, and so on. The bank calculates this automatically — you do not need to do anything.

Is my money safe if the bank fails?

Yes. The FDIC (Federal Deposit Insurance Corporation) insures savings accounts up to $250,000 per account holder per bank. If the bank fails, the FDIC pays you back. This protection applies to all banks that display the FDIC logo, which includes most banks in the United States.