What determines how much interest your savings account earns
The amount of interest you earn depends on three things: the annual percentage yield (APY) your bank offers, how much money you have in the account, and how long it stays there. A bank with a 4.5% APY will pay you roughly 4.5% of your balance per year, but the exact amount varies by bank and changes over time. Banks set their own rates based on what the Federal Reserve does with interest rates, so the rate you see today may be different next month.
The math is straightforward: if you have $10,000 in an account earning 4.5% APY, you earn about $450 per year, or roughly $37.50 per month. But that assumes the rate stays the same and you don't add or withdraw money. In reality, rates change, and most people deposit or spend from savings regularly, so your actual earnings will be different.
Interest compounds, which means you earn interest on the interest you've already earned. How often this happens—daily, monthly, or quarterly—matters. Daily compounding pays slightly more than monthly compounding on the same rate, because your balance grows a little each day and you earn interest on that growth. Most online savings accounts compound daily, which is why they tend to pay more than brick-and-mortar banks offering the same APY.
Key Takeaways
- Your earnings equal your account balance multiplied by the APY, divided by 12 for a monthly estimate, though the exact amount depends on how often interest compounds.
- Banks change their rates frequently in response to Federal Reserve decisions, so a 4.5% rate today may be 3.8% in six months.
- Online banks typically offer higher APYs than traditional banks because they have lower overhead costs.
- Money market accounts and certificates of deposit (CDs) often pay more than savings accounts, but may require larger deposits or lock your money away for a set time.
How to find the current rate at your bank
Your bank's website shows the APY for each account type, usually on the savings account page or in the account details section. The rate displayed is what new deposits earn starting today. If you opened your account months ago, you may be earning a lower rate—banks often lower rates for existing customers when the Federal Reserve cuts rates.
Call your bank's customer service line or visit a branch if you can't find the rate online. Ask specifically for the APY on your account type, not just the interest rate. APY includes the effect of compounding, so it's always higher than the base rate and is the number that matters for your earnings.
If your rate seems low compared to other banks, you can move your money. There's no penalty for closing a savings account and opening one elsewhere. Many people keep savings at an online bank earning 4% or higher while keeping checking at a local bank for convenience.
Why rates differ between banks
Online banks pay more because they don't operate physical branches. They save money on rent, staff, and equipment, and pass some of those savings to customers through higher rates. A bank like Marcus or Ally may offer 4.5% APY while your local credit union offers 0.5% on the same type of account.
Banks also compete for deposits. When rates are rising, banks raise their rates to attract new customers. When rates are falling, they lower rates more slowly, trying to keep existing customers from moving their money. This means the best rate changes month to month, and you may need to shop around to stay competitive.
Credit unions sometimes offer better rates than banks, but only to members. Membership usually requires living or working in a specific area or belonging to a certain group. If you're a member, it's worth checking your credit union's rate against online banks.
How interest compounds and affects your total earnings
Compounding means interest gets added to your balance, and then you earn interest on that new balance. With daily compounding, this happens 365 times per year. With monthly compounding, it happens 12 times. The difference is small on modest balances but adds up over years.
On $10,000 at 4.5% APY with daily compounding, you earn about $450 in the first year. In year two, you earn interest on $10,450, so you earn about $470. By year five, your balance is over $12,400 and you're earning more than $550 per year. This acceleration is compounding at work.
Most online savings accounts compound daily, which is why they're better for long-term savings than accounts that compound monthly or quarterly. The difference between daily and monthly compounding on the same rate is usually less than $5 per year on a $10,000 balance, but it adds up if you're saving for years.
When rates change and what happens to your money
Banks change savings rates without notice. When the Federal Reserve raises rates, banks usually raise their savings rates within days or weeks. When the Fed cuts rates, banks often wait longer before lowering savings rates, trying to keep customers from leaving. This means your rate can go up or down at any time.
Your existing balance keeps earning at the old rate until the bank changes it. Once the rate changes, all new interest is calculated at the new rate. You don't lose money when rates drop—you just earn less going forward. If you had $10,000 earning 4.5% and the rate drops to 3.5%, you still have $10,000, but next month's interest will be smaller.
If your bank's rate drops significantly, you can move your money to a bank with a higher rate. There's no cost to closing a savings account. Some people move their savings every few months to chase the highest available rate, though this is more common among people with large balances where the difference is meaningful.
Comparing savings accounts to other places to keep money
Savings accounts are safe and liquid—you can withdraw money anytime without penalty. Money market accounts work similarly but sometimes require a larger opening deposit and may limit how many withdrawals you can make per month. Both are insured by the FDIC up to $250,000 per account holder per bank.
Certificates of deposit (CDs) lock your money for a set term—usually three months to five years—in exchange for a higher rate. If you withdraw before the term ends, you pay a penalty, usually a few months' worth of interest. CDs make sense if you know you won't need the money for a specific period.
High-yield savings accounts are just savings accounts with higher APYs, usually offered by online banks. They're not a different product—they're the same FDIC-insured account with better rates. There's no catch, though some banks require larger minimum balances or charge monthly fees if your balance drops below a threshold.
How to calculate your earnings and track them
To estimate monthly earnings, multiply your balance by the APY and divide by 12. A $25,000 balance at 4.5% APY earns roughly $93.75 per month. This is an estimate because the actual amount depends on the exact number of days in the month and how your bank calculates daily compounding, but it's close enough for planning.
Your bank sends a statement monthly or quarterly showing interest earned. Check this number against your estimate to make sure it's in the ballpark. If your rate dropped but you weren't notified, the statement will show it. If the interest earned is much lower than expected, call the bank and ask why.
Some banks let you set up alerts when rates change. Check your account settings to see if this option is available. You can also check rate comparison websites like Bankrate or DepositAccounts to see how your bank's rate compares to others, though these sites update periodically rather than in real time.
Frequently Asked Questions
Is the interest I earn on a savings account taxable?
Yes. Interest earned on savings accounts is taxable income. Your bank sends you a 1099-INT form each January if you earned $10 or more in interest during the year. You report this on your tax return as ordinary income. The amount you owe in taxes depends on your tax bracket.
Why is my savings account earning almost nothing?
Traditional banks and credit unions often pay 0.01% to 0.5% APY on savings accounts because they don't need to compete aggressively for deposits. Online banks pay 4% to 5% because they rely entirely on deposits to fund loans. Moving your money to an online bank is free and takes a few days.
Can I lose money in a savings account?
No, savings accounts are FDIC-insured up to $250,000, so your principal is protected. You can only lose purchasing power if inflation rises faster than your interest rate—if you earn 2% but inflation is 4%, your money buys less next year. This is why higher rates matter during inflationary periods.
What happens to my interest if I withdraw money mid-month?
Most banks calculate interest daily based on your balance each day, so if you withdraw money mid-month, you earn interest only on the money that was in the account. If you had $10,000 for 15 days and $5,000 for 15 days, you earn interest on roughly $7,500 for the month.
Should I move my savings to a CD if rates are high?
CDs lock your money away and pay a penalty if you withdraw early, so they only make sense if you're certain you won't need the money for the CD's term. If rates are high now and you think they'll drop, a CD locks in today's rate. If you think rates will rise, keep your money in a savings account where you can move it to a higher-paying account later.