How much your money grows depends on the interest rate and how long it sits there

A savings account grows through interest—money the bank pays you for letting them hold your deposit. The amount you earn depends on three things: how much you deposit, what interest rate the bank offers, and how long the money stays in the account. A $1,000 deposit at 0.01% annual interest earns about $0.10 per year. The same $1,000 at 4.5% annual interest earns about $45 per year. The difference between a low-rate account and a high-rate one can mean hundreds of dollars over time, even on modest deposits.

Interest compounds, meaning you earn interest on your interest. Most savings accounts compound daily or monthly. If you deposit $5,000 at 4.5% compounded daily, after one year you will have roughly $5,230. After five years, roughly $6,200. After ten years, roughly $7,700. The longer your money stays untouched, the more the compounding effect adds up—but only if the interest rate stays the same, which it does not always do.

Key Takeaways

  • Interest rates on savings accounts vary widely by bank, from under 0.01% to over 5%, so comparing rates before opening an account can mean hundreds of dollars in difference over a few years.
  • Money compounds daily or monthly at most banks, meaning you earn interest on the interest you already earned, and the effect grows stronger the longer your money stays in the account.
  • High-yield savings accounts at online banks typically pay 4% to 5.5% annually, while traditional brick-and-mortar banks often pay under 0.5%.
  • Interest rates change over time and are set by each individual bank, not by the government, so the rate you see today may be lower or higher in six months.
  • Money market accounts and certificates of deposit (CDs) may pay higher rates than savings accounts, but often require larger deposits or lock your money away for a set period.

Why interest rates vary so much between banks

Banks set their own interest rates. A large national bank might pay 0.01% on a savings account while an online bank pays 4.75% on the same deposit size. The difference comes down to overhead costs and competition. Online banks have lower costs because they do not maintain physical branches, so they can afford to pay depositors more. Traditional banks have higher costs and often pay less to savers.

Interest rates also move up and down based on what the Federal Reserve does. When the Fed raises its benchmark rate, banks tend to raise savings rates too—though not always by the same amount, and not always right away. When the Fed cuts rates, banks usually cut savings rates within weeks. This means the rate you lock in today may not be the rate you earn next year.

How to calculate what you will earn

The basic formula is: Interest earned = Principal × Annual Rate ÷ 365 × Number of Days. If you have $10,000 at 4% annual interest, you earn roughly $400 per year, or about $1.10 per day. Most banks do the math for you and deposit interest monthly or daily, so you do not need to calculate it yourself.

For longer time periods, compounding makes the math more complex, but online calculators handle it. Search "savings account calculator" and enter your deposit amount, the annual interest rate, and how many years you plan to keep the money. The calculator will show you the final balance and total interest earned. This is useful for comparing accounts before you open one.

The difference between high-yield and standard savings accounts

A high-yield savings account typically pays 4% to 5.5% annually, while a standard savings account at a traditional bank pays under 0.5%. On a $10,000 deposit, the difference is roughly $400 to $500 per year. Over five years, a high-yield account could earn $2,000 to $2,500 more than a standard account.

High-yield accounts are usually offered by online banks or credit unions. They have the same federal insurance protection as standard accounts—your money is insured up to $250,000 per depositor per bank. The trade-off is that you cannot walk into a branch to deposit cash or speak to someone in person. Most high-yield accounts let you transfer money in and out electronically, and some allow you to link an external checking account for easy access.

Money market accounts and certificates of deposit pay more, but with strings attached

A money market account is a hybrid between a savings account and a checking account. It typically pays higher interest than a savings account—sometimes 4% to 5%—but often requires a larger minimum deposit, sometimes $2,500 or more. It may also limit how many withdrawals you can make per month.

A certificate of deposit (CD) locks your money away for a set period—three months, six months, one year, five years, or longer. In exchange, the bank pays a higher rate, sometimes 5% or more. If you withdraw the money before the CD matures, you pay a penalty, usually a few months' worth of interest. CDs make sense if you know you will not need the money for a specific length of time and want a may provide rate.

What happens when interest rates drop

If you have money in a savings account earning 5% and the Fed cuts rates, your bank will likely cut your rate too within a few weeks or months. You do not lose the money you already earned, but future interest will be lower. This is why some people move money to a CD when rates are high—the CD rate is locked in for the full term, even if rates drop later.

If rates drop significantly, you may want to move your money to a different bank offering a higher rate. There is no penalty for closing a savings account and moving to another bank. You can open a new account at a different institution and transfer your balance electronically. This is a normal practice and banks expect it.

How federal insurance protects your deposit

The Federal Deposit Insurance Corporation (FDIC) insures savings accounts at member banks up to $250,000 per depositor per bank. This means if the bank fails, you get your money back, including any interest earned up to the failure date. If you have more than $250,000, you can spread it across multiple banks to keep all of it insured.

Credit unions offer similar protection through the National Credit Union Administration (NCUA), also up to $250,000 per member per institution. This insurance does not depend on the interest rate the bank pays—a high-yield account is just as protected as a low-rate account.

Frequently Asked Questions

How often does interest get added to my account?

Most banks add interest monthly or daily. Daily compounding means interest is calculated every day and added to your balance, so you earn interest on interest more frequently. Monthly compounding adds interest once a month. The difference is small on modest balances but adds up over years. Check your bank's disclosure to see how often they compound.

Can I lose money in a savings account?

No. Your principal—the money you deposit—is protected by federal insurance and cannot go down. Interest rates can drop, so you may earn less than you expected, but you will not lose what you put in. The only exception is if you withdraw money and pay a penalty, which is rare for savings accounts (more common with CDs).

Is it better to keep money in a savings account or invest it?

Savings accounts are safe and insured but earn modest returns. Investments like stocks and bonds can earn more over time but carry risk of loss. Savings accounts are for money you need to access within a few years or want to keep safe. Investments are for longer time horizons and higher risk tolerance. Many people use both.

What is the highest interest rate I can find right now?

Rates change frequently and vary by bank. As of early 2024, some online banks offer 4.5% to 5.5% on high-yield savings accounts, but this changes as the Fed adjusts its rates. Check current rates at comparison sites or directly on bank websites. Rates are not may provide and can drop at any time.

Do I have to pay taxes on savings account interest?

Yes. Interest earned on a savings account is taxable income. Banks send you a 1099-INT form at tax time if you earned $10 or more in interest. You report this on your tax return. The tax owed depends on your overall income and tax bracket. Keep records of interest earned throughout the year.