Banks lend out your deposit money and keep the difference between what they pay you and what borrowers pay them

When you put money in a savings account, the bank doesn't lock it in a vault with your name on it. Instead, the bank uses that money to make loans to other customers — mortgages, car loans, business loans, credit cards. The borrower pays the bank interest on the loan. The bank pays you a smaller amount of interest on your deposit. The gap between those two rates is how the bank makes its profit from your account.

This arrangement benefits all three parties. You earn money on savings you're not using right now. The borrower gets access to money they need. The bank earns a return for managing both sides of the transaction and taking on the risk that a borrower might not repay.

The bank's profit margin depends on the interest rate environment. When the Federal Reserve sets rates high, banks can charge borrowers more and still pay depositors a competitive rate. When rates are low, the spread shrinks, and banks earn less per dollar deposited.

Key Takeaways

  • Banks lend your deposit money to other customers and profit from the difference between the interest rate they pay you and the rate borrowers pay them.
  • The Federal Reserve's interest rate decisions directly affect how much interest banks can offer on savings accounts and how much they charge borrowers.
  • Your deposits are insured up to $250,000 per account type at FDIC-insured banks, so the bank's lending activities don't put your money at risk.
  • Banks also earn money from deposits through fees, investment services, and other products beyond the basic lending spread.
  • The interest rate a bank offers you reflects both the Fed's rate environment and the bank's own funding costs and competitive position.

The interest rate spread: what banks actually earn

The spread is the percentage-point difference between what a bank pays depositors and what it charges borrowers. If a bank pays you 4% annual interest on savings but charges a borrower 7% on a personal loan, the spread is 3 percentage points. That 3% is the bank's gross profit on that particular transaction, before the bank's own operating costs.

A spread of 2 to 3 percentage points is typical for retail banks in normal market conditions. During periods of very low interest rates, spreads can narrow to less than 1 percentage point, which is why banks sometimes offer almost no interest on savings accounts. During periods of high rates, spreads can widen, which is why you might see savings accounts offering 4% or 5% interest.

The spread isn't the same for every loan type. Mortgages often have smaller spreads because they're backed by real estate and considered lower-risk. Credit cards have much larger spreads because they're unsecured and carry higher default risk. The bank balances the risk of each loan type against the spread it needs to stay profitable.

How the Federal Reserve's interest rate decisions affect your deposit rate

The Federal Reserve doesn't set the interest rate your bank pays on deposits. But the Fed's benchmark rate — called the federal funds rate — acts as a floor that influences all other rates in the economy. When the Fed raises its rate, banks can charge borrowers more, which gives them room to pay depositors more while maintaining their spread. When the Fed lowers its rate, banks have less room to maneuver, and deposit rates often fall.

Banks don't pass along Fed rate changes when ready. A bank might wait weeks or months before raising the interest rate on savings accounts, even after the Fed raises its benchmark rate. This delay is intentional — it lets the bank widen its spread temporarily. Conversely, banks often lower deposit rates quickly when the Fed cuts rates, because they want to protect their profit margin.

This is why shopping around for savings accounts matters. Different banks respond to Fed rate changes at different speeds and to different degrees. A credit union or online bank might offer 4.5% on savings while a large national bank offers 3.5%, even though both are responding to the same Fed rate environment.

Why banks need deposits to make loans

Banks are required by law to keep a certain amount of capital on hand — money they own outright, not borrowed. But they fund most of their lending through deposits. When you put $5,000 in a savings account, the bank can lend out most of that $5,000 (they keep a small reserve) and earn interest on the loan.

This is why banks compete for deposits. A bank with more deposits can make more loans and earn more interest income. A bank with fewer deposits has to borrow money from other banks or the Federal Reserve at higher rates, which cuts into their profit margin. During periods when deposits are scarce, banks raise the interest rates they offer to attract more money.

The 2023 banking crisis illustrated this dynamic. Some banks had made long-term loans at low rates before interest rates rose. When depositors started moving their money to higher-yielding accounts elsewhere, those banks couldn't raise enough deposits to cover their costs, and several failed. This is an extreme case, but it shows why the deposit-to-lending relationship is central to how banks operate.

Your deposits are protected even when banks lend them out

The fact that banks lend out your money can sound risky, but your deposits are insured. The Federal Deposit Insurance Corporation (FDIC) insures deposits up to $250,000 per depositor, per bank, per account type. This means if the bank fails and can't repay depositors, the FDIC steps in and covers your balance up to that limit.

The FDIC insurance is funded by banks themselves, not by taxpayers. Banks pay a small insurance premium based on the total deposits they hold. This cost is built into the bank's operating expenses and affects how much interest they can afford to pay you, but it's a necessary part of the system.

Credit unions offer similar protection through the National Credit Union Administration (NCUA), which insures deposits up to $250,000 per member account. The insurance coverage is the same, but credit unions are structured differently — they're member-owned cooperatives rather than for-profit corporations.

Other ways banks earn money from deposits

The interest spread is the primary way banks profit from deposits, but it's not the only way. Banks also charge monthly maintenance fees on checking accounts, overdraft fees when you spend more than your balance, and ATM fees when you use another bank's machine. Some banks charge fees for wire transfers, cashier's checks, or account inactivity.

Banks also earn money by selling other products to depositors — investment accounts, insurance, credit cards, and wealth management services. A customer who opens a savings account might eventually open a checking account, get a mortgage, and invest through the bank's brokerage arm. The deposit is often the entry point to a longer-term relationship that generates multiple revenue streams.

Fee income has become increasingly important to banks as interest rate spreads have narrowed. A bank that can't earn much from lending might rely more heavily on fees to maintain profitability. This is one reason why some banks charge more fees than others — they're compensating for a narrower lending spread or a different business model.

Why interest rates on deposits vary so much between banks

If all banks operate under the same Federal Reserve rate, why does one bank offer 4.5% on savings while another offers 0.5%? The answer is competition, funding costs, and business strategy.

Online banks typically offer higher deposit rates because they have lower overhead costs — no physical branches, fewer employees, lower real estate expenses. They can afford to pay more interest and still be profitable. Large national banks with extensive branch networks have higher costs and often offer lower rates, betting that customers will stay for convenience rather than yield.

Banks also adjust rates based on how much deposit funding they need. A bank that's flush with deposits might lower its rates because it doesn't need to attract more money. A bank that's losing deposits to competitors might raise rates to stem the outflow. During the 2023 banking crisis, some banks raised rates dramatically to keep deposits from fleeing.

Your credit history and account balance can also affect the rate you're offered, though this is less common for savings accounts than for other products. Some banks offer tiered rates — higher interest if you maintain a larger balance.

What happens to your money when interest rates are very low

When the Federal Reserve keeps rates very low — as it did from 2008 to 2015 and again from 2020 to 2022 — banks earn very little from the spread between deposit rates and loan rates. Deposit rates often fall to near zero, sometimes literally 0.01% annually. At that point, the bank is earning almost nothing from your savings account.

This is frustrating for savers, but it's intentional policy. The Fed lowers rates to encourage borrowing and spending during economic downturns. Banks lower deposit rates because they have no incentive to pay more when they can't charge borrowers much either. The tradeoff is that your money loses purchasing power to inflation while earning almost nothing.

During these periods, some people move money to money market accounts, certificates of deposit (CDs), or other products that might offer slightly higher rates. Others straightforward accept the low rate as the cost of keeping money safe and accessible. The choice depends on your timeline and how much you need access to the money.

Frequently Asked Questions

Can a bank go bankrupt if too many borrowers don't repay their loans?

Yes, but the FDIC insurance protects your deposits even if the bank fails. The bank's losses come from its own capital first, then from the FDIC insurance fund. Your $250,000 per account type is covered regardless of how many loans go bad. The bank's shareholders and executives bear the losses, not depositors.

Do I earn interest on money in my checking account?

Most checking accounts earn little to no interest, even though the bank is lending out that money. Banks treat checking accounts as transaction accounts rather than savings vehicles. Some banks offer interest-bearing checking accounts, but the rates are usually much lower than savings accounts. If you have money you won't need for a while, a savings account or money market account will earn more.

What's the difference between a savings account and a money market account?

Both are deposit accounts that earn interest, and both are FDIC insured up to $250,000. Money market accounts often offer higher interest rates in exchange for requiring a larger minimum balance and limiting how often you can withdraw. Savings accounts are more flexible but typically pay less. The bank's profit mechanism is the same for both — they lend out your money and keep the spread.

Why do some banks offer much higher interest rates than others?

Online banks and credit unions often offer higher rates because they have lower operating costs than large national banks with branch networks. Banks also adjust rates based on how much deposit funding they need at any given time. Shopping around for the highest rate can significantly increase your earnings on savings, especially in higher-rate environments.

Is my money safe if the bank lends it out and the borrower doesn't repay?

Yes. Your deposit is insured by the FDIC up to $250,000, regardless of whether the bank's loans perform well or poorly. The bank absorbs loan losses from its own capital and profits. Your account is protected by insurance, not by the bank's lending success.