What you earn depends on the bank's rate and how much you have saved
The amount of interest you earn in a savings account is determined by two things: the annual percentage yield (APY) the bank offers, and the balance you keep in the account. A bank offering 4.5% APY will pay you more interest than one offering 0.01% APY — but only if you actually have money sitting there to earn it on.
The interest is calculated daily or monthly (depending on the bank), but you typically see it added to your account once a month. The longer your money stays in the account, the more interest accumulates. This is different from a checking account, where banks usually pay little to no interest.
Right now, rates vary widely. Online banks often pay higher rates than brick-and-mortar banks because they have lower overhead costs. A bank down the street might offer 0.01% APY, while an online bank offers 4.5% or higher. The difference between these two is enormous — on $10,000, you'd earn roughly $1 per year at 0.01%, but $450 per year at 4.5%.
Key Takeaways
- Interest earned depends on both the APY rate and your account balance — a higher rate on a small balance may earn less than a lower rate on a large balance.
- Online banks typically offer higher APY rates than traditional banks because they have fewer physical locations and lower costs.
- Interest is usually calculated daily but added to your account monthly, so the exact timing varies by bank.
- Rates change over time and vary between banks, so comparing rates before opening an account can significantly increase what you earn.
- You earn interest only on money that stays in the savings account — withdrawals reduce your balance and the interest you earn.
How the math works: APY, balance, and time
To understand what you'll actually earn, you need to see how these three pieces fit together. APY is the yearly rate. Your balance is how much money sits in the account. And time is how long it stays there.
Here's a straightforward example: if you have $5,000 in an account earning 4.5% APY, you'd earn roughly $225 in one year (before any withdrawals). If you have $10,000 at the same rate, you'd earn roughly $450. Double the balance, double the interest.
But if you withdraw $2,500 after six months, the math changes. You'd earn interest on $5,000 for the first six months, then on $2,500 for the second six months. The total would be less than if you'd left the full $5,000 in for the entire year.
Banks calculate this daily, not yearly. They divide the APY by 365 (or 366 in a leap year) to get a daily rate, then explore that rate to your balance each day. At the end of the month, they add up all those daily amounts and deposit the total interest into your account.
Why rates are different at different banks
Banks set their own APY rates based on what they need to attract deposits and what they can afford to pay. Online banks — those without physical branches — typically offer higher rates because they spend less money on buildings, staff, and equipment. They pass some of those savings to customers in the form of higher interest.
Traditional banks with branches in your neighborhood often pay lower rates. They have more expenses, and they rely on other ways to make money (like charging fees). Some customers are willing to accept lower interest in exchange for the ability to walk into a branch and speak to someone in person.
Rates also move up and down based on what the Federal Reserve does. When the Fed raises its benchmark rate, banks tend to raise the rates they offer on savings accounts. When the Fed lowers rates, banks usually lower theirs too. This means the rate you see today might be different in three months.
Where to find current rates and compare them
Banks publish their APY rates on their websites, usually on the savings account product page. You'll see the rate clearly listed, along with any minimum balance requirements. Some banks offer different rates depending on how much you deposit — a higher rate if you keep $25,000 or more, for example.
To compare rates across banks, you can visit each bank's website individually, or use financial websites that list current rates from multiple banks. These comparison sites update regularly, though not always in real time. The rate shown online is usually the rate you'll receive when you open an account, but confirm it before you deposit money.
When comparing, also check whether there are any fees that could reduce your earnings. Some banks charge a monthly maintenance fee, an inactivity fee, or a fee for falling below a minimum balance. A high interest rate doesn't help if fees eat into your earnings.
How interest compounds over time
Interest compounds when the bank adds interest to your account, and then you earn interest on that interest in the next period. In a savings account, this happens monthly or daily depending on the bank.
The effect is small in the short term but noticeable over years. If you have $10,000 earning 4.5% APY and never withdraw it, after one year you'd have $10,450. After two years, you'd have roughly $10,920 — not just $10,900. That extra $20 came from earning interest on the interest you already earned.
The longer your money stays in the account, the more compounding works in your favor. This is why starting early, even with a small amount, can make a real difference over time.
What happens if you withdraw money before the end of the month
Most savings accounts calculate interest daily, so you earn interest on your balance right up until you withdraw. If you withdraw money mid-month, you lose the interest you would have earned on that amount for the rest of the month, but you keep the interest already earned.
Some banks have restrictions on how often you can withdraw from a savings account. Federal rules used to limit withdrawals to six per month, but that rule was suspended. However, individual banks may still have their own limits or may charge a fee for frequent withdrawals. Check your bank's terms before opening an account if you think you'll need to withdraw regularly.
If you need to access your money frequently, a savings account might not be the best choice. A checking account gives you unlimited withdrawals, though it typically earns little or no interest. Some banks offer money market accounts, which are a middle ground — they earn interest and allow some withdrawals, but usually fewer than a checking account.
Why your savings account interest might be lower than you expect
Even at a bank advertising a high rate, you might earn less interest than the APY suggests. This usually happens for one of three reasons: you're not keeping the full balance for the entire year, the rate changed during the year, or you're looking at an introductory rate that only lasts a few months.
Some banks offer a promotional rate for new customers — perhaps 5% APY for the first three months, then 4% after that. If you open the account and leave the money untouched for a year, you'd earn more in the first three months than the remaining nine months. Read the fine print to see when a promotional rate expires.
Also, if you withdraw money, your balance goes down and so does your interest. If you deposit $10,000 on day one and withdraw $5,000 on day 15, you're earning interest on a lower average balance for most of the month. The interest you receive reflects that lower balance.
Frequently Asked Questions
Is the interest I earn on a savings account taxed?
Yes. Interest earned in a savings account is considered income by the IRS. 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 you owe in taxes depends on your overall income and tax bracket.
Can I lose money in a savings account?
No. Your deposits are protected by the FDIC (Federal Deposit Insurance Corporation) up to $250,000 per account holder per bank. You won't lose your principal, and you'll earn whatever interest the bank pays. The only way your balance goes down is if you withdraw money or if fees are charged.
Why do some banks pay almost no interest?
Banks with physical branches have higher costs and may not need to offer high rates to attract deposits. They rely on other revenue sources like fees and loans. Online banks compete primarily on interest rates, so they offer higher rates to attract customers. Shop around — there's no reason to accept 0.01% when other banks pay 4% or more.
Does it matter if interest is compounded daily or monthly?
Daily compounding earns slightly more than monthly compounding over time, but the difference is small — usually a few dollars per year on a typical balance. Both are better than no compounding. Focus more on finding the highest APY rate available than on the compounding frequency.
What if I move my money to a different bank — do I lose the interest I already earned?
No. Interest that has already been added to your account is yours to keep. When you transfer money to another bank, you take that interest with you. You only lose future interest — the interest you would have earned if you'd left the money in the original account.