Interest is how a bank pays you to keep money there

A savings account earns money through interest—a percentage of your balance that the bank adds to your account on a set schedule, usually monthly or daily. The bank lends out the money you deposit to other customers as mortgages, car loans, and business credit lines. They keep the difference between what they pay you in interest and what they charge borrowers. You earn money straightforward by holding the account open and maintaining a balance.

The amount you earn depends on two things: how much money sits in the account and what interest rate the bank offers. A $5,000 balance at 4.5% annual interest earns roughly $225 per year. The same balance at 0.01% earns 50 cents per year. The difference between a high-yield savings account and a traditional bank savings account can be hundreds of dollars annually on the same deposit.

Interest compounds, meaning you earn money on the interest you already earned. If your account compounds daily, the bank calculates interest on your balance each day and adds it to your account. The next day, you earn interest on that slightly larger balance. Over months and years, compounding turns a modest rate into meaningful growth.

Key Takeaways

  • Banks pay interest on savings account balances as a percentage of what you deposit, and the rate varies widely between institutions—from under 0.01% to over 5% depending on current market conditions and account type.
  • Interest compounds daily or monthly, meaning you earn returns on the interest already added to your account, which accelerates growth over time.
  • High-yield savings accounts at online banks typically offer rates 10 to 50 times higher than traditional brick-and-mortar bank savings accounts.
  • The Federal Reserve's interest rate decisions directly affect what banks offer savers, so rates rise and fall over years, not within a single account.
  • Your earnings are taxed as ordinary income, and banks report interest over $10 to the IRS on a 1099-INT form.

How interest rates are set and why they change

Banks do not choose their interest rates in isolation. The Federal Reserve sets a target range for the federal funds rate—the rate at which banks lend to each other overnight. When the Fed raises this rate, banks raise the rates they offer on savings accounts. When the Fed lowers it, savings rates fall. This happens over months, not days, and the changes are gradual.

In 2022 and 2023, the Fed raised rates aggressively to fight inflation, and savings account rates climbed from near zero to 4% and above at competitive banks. In earlier years, rates hovered around 0.01% because the Fed kept its rate near zero. The rate you see today is not permanent—it will shift as the Fed's policy changes.

Banks also compete for deposits. An online bank with lower overhead costs can offer higher rates than a traditional bank with thousands of branches. If you shop around, you will find rates varying by 4% or more between institutions on the same day. Moving your money to a higher-rate account costs nothing and takes a few days.

The difference between savings accounts and money market accounts

A money market account is a hybrid between a savings account and a checking account. It typically offers a higher interest rate than a standard savings account but comes with limited check-writing or debit card access. Some money market accounts let you write three to six checks per month; others offer none.

Both accounts are insured by the FDIC (Federal Deposit Insurance Corporation) up to $250,000 per depositor per bank. Both earn interest on your balance. The main trade-off is access: a savings account gives you unlimited transfers and withdrawals (though federal rules once limited this to six per month—that rule was suspended, but some banks still enforce it). A money market account restricts how often you can move money out, which is why banks pay slightly more interest.

For most people building an emergency fund or saving toward a goal, a high-yield savings account offers better terms than a money market account. You get competitive interest rates without the withdrawal restrictions.

How to calculate what you will earn

Banks state interest rates as an APY, or Annual Percentage Yield. This is the total return you would earn in one year if you made no deposits or withdrawals and rates stayed constant. A $10,000 deposit at 4.5% APY earns $450 in one year, assuming the rate does not change.

To estimate earnings on your own balance, multiply your account balance by the APY and divide by 12 for a monthly estimate. A $25,000 balance at 4.5% APY earns roughly $1,125 per year, or about $94 per month. If the rate drops to 3%, that same balance earns $750 per year, or $62 per month.

The actual amount varies slightly depending on how the bank compounds interest—daily compounding produces slightly more than monthly compounding on the same rate. Most online banks compound daily, which is why they advertise their APY prominently. The difference is small on typical balances but adds up over years.

Tax treatment of savings account interest

Interest you earn is taxed as ordinary income at your regular tax rate. If you earn $500 in interest and your tax bracket is 22%, you owe roughly $110 in federal tax on that interest. State income tax may explore as well, depending on where you live.

Banks report interest earnings to the IRS on a 1099-INT form if you earn more than $10 in interest during the year. You receive a copy by January 31 of the following year. You must report this income on your tax return even if the bank does not send a 1099-INT—the IRS tracks it.

This tax liability is one reason to compare rates carefully. Earning $500 at a 5% rate is better than earning $100 at a 1% rate, even after taxes, because you keep more money. But it also means that very high balances in low-rate accounts can trigger unexpected tax bills if you are not tracking the interest.

Why some accounts offer higher rates than others

Online banks offer higher rates because they have no physical branches, no tellers, and lower operating costs. They pass those savings to depositors in the form of higher interest rates. A bank like Ally or Marcus can offer 4% or higher on savings accounts because they spend almost nothing on overhead.

Traditional banks—the ones with buildings on your street—typically offer 0.01% to 0.5% on savings accounts. They use deposits to fund their branch network and staff. You are paying for convenience and in-person service with lower interest earnings.

Credit unions sometimes offer competitive rates, though not always. Some credit unions offer 3% to 5% on savings, while others offer less than 1%. The rate depends on the credit union's size, funding strategy, and current lending demand. If you belong to a credit union, ask what rate they offer before moving money to an online bank.

How to move money between accounts without losing earnings

Transferring money from a low-rate account to a high-rate account takes three to five business days through an ACH transfer (Automated Clearing House). During that time, the money sits in transit and earns no interest at either institution. On small amounts, this delay costs almost nothing. On $50,000, a three-day delay at a 4% rate costs about $16 in lost interest.

You can minimize this by timing transfers to coincide with when interest is posted. Most banks post interest on the last day of the month or the first day of the next month. If you initiate a transfer the day after interest posts, you capture that month's earnings before the money leaves.

Some banks offer wire transfers, which move money the same day but typically cost $15 to $30. For most savers, the ACH transfer delay is worth the fee savings. Only use a wire if you are moving a very large balance and the interest cost of the delay exceeds the wire fee.

Frequently Asked Questions

Can I lose money in a savings account?

No. FDIC insurance protects your balance up to $250,000 per bank. The interest rate can drop, which means you earn less going forward, but your principal is safe. If a bank fails, the FDIC pays you back in full up to the limit.

What happens if interest rates drop after I open an account?

The bank will lower the rate on your account to match the new market rate. You have no obligation to stay—you can move your money to another bank offering a better rate. There is no penalty for closing a savings account and transferring the balance elsewhere.

Do I need a minimum balance to earn interest?

Most online banks have no minimum balance requirement. Some traditional banks require $500 or $1,000 to open a savings account or to earn the advertised rate. Check the account terms before opening. If you have less than the minimum, the bank may charge a monthly fee that wipes out any interest earned.

How often does interest get added to my account?

Banks compound and post interest on different schedules. Most online banks compound daily and post monthly, meaning they calculate interest every day but add it to your account once a month. Some post quarterly or annually. The more frequently interest compounds, the slightly more you earn, but the difference is small on typical balances.

Is a savings account the best place to keep money long-term?

A savings account is safe and liquid, meaning you can access your money quickly. But over decades, inflation erodes the purchasing power of money sitting in savings, even at 4% or 5% interest. For money you will not need for five years or more, other options like CDs (certificates of deposit) or investments may offer better returns, though they come with different risks and restrictions.