What Your Savings Account Earns Depends on the Interest Rate and How Long You Keep Money There
A savings account earns money through interest—a percentage of your balance that the bank pays you each month or year. The amount you earn depends on three things: how much money sits in the account, what interest rate the bank offers, and how long the money stays there. A $10,000 balance at 4.5% annual interest earns roughly $450 per year, or about $37.50 per month. The same $10,000 at 0.01% interest earns about $1 per year. The difference between a high-yield account and a traditional bank account can mean hundreds of dollars annually on the same balance.
Interest rates change constantly and vary widely between banks. Online banks typically offer higher rates than brick-and-mortar banks because their operating costs are lower. Credit unions sometimes offer competitive rates to members. Banks also change their rates based on what the Federal Reserve does with its benchmark rate—when the Fed raises rates, savings account rates usually rise within weeks or months. When the Fed cuts rates, bank rates fall too, sometimes immediately.
Key Takeaways
- Your earnings equal your balance multiplied by the annual interest rate divided by 12 (for monthly earnings), so a $5,000 balance at 4% earns about $16.67 per month.
- Online banks currently offer rates between 4% and 5.35%, while traditional banks often offer 0.01% to 0.5%, creating a difference of hundreds of dollars per year on the same balance.
- Interest rates change when the Federal Reserve adjusts its benchmark rate, and banks may raise or lower their rates within days or weeks of a Fed announcement.
- Some accounts compound interest daily (meaning you earn interest on your interest), while others compound monthly or annually, which slightly increases your total earnings over time.
How to Calculate What You'll Earn
The basic formula is straightforward: multiply your account balance by the annual interest rate, then divide by 12 to get your monthly earnings. A $20,000 balance at 4.5% annual interest earns $20,000 × 0.045 ÷ 12 = $75 per month. If you add $500 to the account each month, your balance grows and so does your monthly interest—the bank recalculates based on your new balance.
Most banks compound interest daily, meaning they calculate what you've earned each day and add it to your balance, so the next day's interest is calculated on a slightly larger amount. This compounding effect is small on savings accounts but adds up over years. A $10,000 balance earning 4.5% annually grows to $10,450 in one year with daily compounding, versus $10,450 with annual compounding—the difference is negligible on savings accounts but matters more on larger balances or longer time periods.
You can find online calculators on most bank websites that do this math for you. Enter your balance, the interest rate, and how many months you plan to keep the money there, and the calculator shows your projected earnings. These projections assume the rate stays the same, which rarely happens—rates typically change several times per year.
Why Interest Rates Vary So Much Between Banks
Online banks offer higher rates because they have lower overhead costs. They don't maintain physical branches, pay as many employees, or lease office space. They pass those savings to customers through higher interest rates. A bank like Ally or Marcus might offer 4.5% while Chase or Bank of America offers 0.01% on the same type of account—the difference reflects their business model, not the safety of your money.
Credit unions sometimes compete with online banks on rates because they're member-owned rather than profit-driven. Some credit unions offer 4% to 5% on savings accounts, especially if you maintain a minimum balance or set up direct deposit. However, credit unions vary widely—some offer rates as low as traditional banks. You have to check your specific credit union's current rate.
Banks also tier their rates by balance. Some offer 4.5% on balances up to $25,000 and 4.0% on anything above that. Others offer the same rate regardless of balance. A few banks offer promotional rates for new customers—5% for the first three months, then dropping to 4%—so the rate you see advertised may not be permanent.
How Federal Reserve Rate Changes Affect Your Earnings
The Federal Reserve sets a benchmark interest rate that influences what banks charge for loans and what they pay on savings. When the Fed raises its benchmark rate, banks typically raise savings account rates within days or weeks. When the Fed cuts rates, bank rates fall too, sometimes immediately. Between March 2022 and July 2023, the Fed raised rates aggressively, and savings account rates climbed from near 0% to 4.5% or higher. When the Fed paused rate increases in 2024, new account rates stabilized rather than climbing further.
You can track the Fed's rate decisions on the Federal Reserve's website, which publishes the benchmark rate after each meeting. Financial news outlets also cover rate changes immediately. If you're shopping for a savings account, check whether the bank's rate is likely to stay competitive—banks that were early to raise rates during the 2022–2023 cycle have generally kept rates higher than banks that moved slowly.
Comparing Earnings Across Different Account Types
A traditional savings account and a money market account earn interest the same way, but money market accounts sometimes offer slightly higher rates in exchange for requiring a larger minimum balance (often $2,500 to $10,000). A certificate of deposit (CD) locks your money away for a set period—three months, one year, five years—and pays a fixed rate that doesn't change. CDs currently offer rates 0.5% to 1% higher than savings accounts because the bank knows your money will stay put. If you withdraw early, you pay a penalty that can erase months of interest.
A high-yield savings account is simply a savings account with a higher interest rate—the term doesn't have a legal definition, but it typically means 4% or higher. These accounts have the same FDIC insurance protection as regular savings accounts and the same access to your money (you can withdraw anytime without penalty). The only trade-off is that rates can change, whereas a CD rate is locked in.
| Account Type | Typical Current Rate | Minimum Balance | Withdrawal Penalty |
|---|---|---|---|
| Traditional savings account | 0.01% to 0.5% | $0 to $500 | None |
| High-yield savings account | 4% to 5.35% | $0 to $25,000 | None |
| Money market account | 4% to 5.25% | $2,500 to $10,000 | None |
| 3-month CD | 4.5% to 5.5% | $500 to $2,500 | 3 months' interest |
| 1-year CD | 4.5% to 5.5% | $500 to $2,500 | 3 to 6 months' interest |
What Reduces Your Earnings or Wipes Them Out
Monthly maintenance fees are the biggest threat to your interest earnings. Some banks charge $5 to $15 per month if your balance falls below a minimum or if you don't set up direct deposit. On a $5,000 balance earning 4.5% annually ($18.75 per month), a $10 monthly fee wipes out more than half your earnings. Most online banks and credit unions don't charge maintenance fees, but traditional banks often do. Always check the fee schedule before opening an account.
Inactivity fees are less common but still exist at some banks—if you don't make a deposit or withdrawal for six months or a year, the bank may charge a fee. Read the account agreement or call the bank to confirm there are no hidden fees. The interest you earn is only money in your pocket if the bank isn't taking it back through fees.
Frequently Asked Questions
Can I earn more money by moving my savings to a different bank?
Yes, potentially hundreds of dollars per year on the same balance. A $50,000 balance earning 0.01% at a traditional bank earns $5 annually. The same balance at 4.5% earns $2,250 per year—a difference of $2,245. Moving to a higher-rate bank makes sense if you have a balance over $5,000 and plan to keep it there for at least several months.
What happens to my interest rate if the Federal Reserve cuts rates?
Your bank's rate will likely fall within days or weeks, though the exact timing varies. Banks are not required to lower rates immediately, but they usually do to stay competitive. If you're in a CD, your rate is locked in and won't change until the CD matures. If you're in a savings account, the rate can change anytime.
Is my money safe in a high-yield savings account?
Yes, as long as the bank is FDIC-insured, which nearly all banks are. FDIC insurance covers up to $250,000 per account holder per bank, so your balance is protected even if the bank fails. The interest rate has no effect on safety—a 4.5% account is just as safe as a 0.01% account at the same bank.
Do I have to pay taxes on the interest I earn?
Yes, interest income is taxable as ordinary income. The bank sends you a 1099-INT form at tax time showing how much interest you earned. You report this on your tax return. If you earned $100 in interest, you owe taxes on that $100 at your normal tax rate, which varies based on your income level.
Should I open a CD instead of a savings account to earn more?
CDs currently offer rates only slightly higher than savings accounts—often 0.5% to 1% more. A $10,000 CD at 5.5% earns $550 annually versus $450 in a savings account at 4.5%, a difference of $100. The trade-off is that your money is locked away and you pay a penalty if you need it early. A savings account gives you flexibility to withdraw anytime without penalty, which matters if you might need the money.