Banks pay interest on deposits because they lend that money out and earn more from borrowers than they pay you
When you deposit money in a savings account or certificate of deposit, the bank does not lock your cash in a vault. Instead, the bank lends most of it to other customers as mortgages, car loans, and business loans. Those borrowers pay the bank interest rates much higher than what the bank pays you. The difference—called the net interest margin—is how the bank makes profit.
A simple example: you might earn 4.5% annual interest on a savings account. The bank turns around and lends that same money to a mortgage borrower at 6.5% or 7%. The bank keeps the spread. The more deposits a bank holds, the more money it has to lend out, and the more interest income it generates. Paying you interest is the cost of getting you to hand over that money in the first place.
Key Takeaways
- Banks lend out the money you deposit and earn interest from borrowers at rates higher than what they pay depositors.
- The gap between what banks pay you and what they charge borrowers is their primary source of profit.
- Interest rates on deposits rise when the Federal Reserve raises its benchmark rate, because banks compete harder for deposits when borrowing costs go up.
- Banks must hold a portion of deposits in reserve and cannot lend out every dollar, which is why they do not pass along the full borrowing rate to you.
- Online banks often pay higher deposit interest than traditional banks because they have lower overhead costs and can afford to offer better rates.
How the Federal Reserve influences what banks pay you
The Federal Reserve sets a benchmark interest rate—currently a range rather than a single number—that influences what banks charge each other to borrow overnight. When the Fed raises this rate, banks' own borrowing costs go up. To offset that cost, banks compete more aggressively for deposits by raising the interest rates they offer to savers. When the Fed cuts rates, banks lower deposit rates because they need deposits less urgently.
This is why deposit rates jumped sharply in 2022 and 2023: the Fed raised its benchmark rate from near zero to over 5% in less than a year. Banks suddenly needed deposits badly and began offering 4%, 5%, and even 5.5% on savings accounts and CDs. Before that period, rates had been near zero for years because the Fed's benchmark was near zero.
You do not see the Fed's rate change instantly in your account. Banks adjust deposit rates on their own schedule, and some move faster than others. Online banks typically adjust within days; traditional banks may take weeks or longer.
Reserve requirements and why you do not get the full borrowing rate
Banks cannot lend out every dollar you deposit. The Federal Reserve requires banks to hold a minimum percentage of deposits in reserve—money that stays in the vault or at the Fed and cannot be loaned out. This reserve requirement exists to ensure banks can handle withdrawals and stay solvent if loans go bad.
Because banks must set aside a portion of your deposit, they earn less interest on it than they would if they could lend it all. That is one reason the rate they pay you is always lower than the rate they charge borrowers. If a bank had to hold 10% in reserve, it can only lend 90% of your deposit. The interest it earns on that 90% has to cover the interest it pays you on 100%, plus operating costs and profit.
Operating costs and competition between banks
Banks have significant expenses: employee salaries, branch buildings, technology systems, insurance, and regulatory compliance. These costs come out of the interest margin. A bank that operates 500 branches nationwide has higher overhead than an online bank with no physical locations. That is why online banks often pay higher interest rates on savings accounts and CDs—they spend less on buildings and staff, so they can afford to pass more of their profit margin to depositors.
Competition also shapes deposit rates. In markets where multiple banks offer high-yield savings accounts, rates tend to be higher because banks must compete for your money. In areas with fewer options, rates may be lower. National banks and online banks set rates based on national competition; smaller regional banks may set different rates based on local demand for deposits.
Why banks still pay interest even when rates are low
Even when the Federal Reserve's benchmark rate is near zero, banks still pay some interest on deposits—though it may be 0.01% or lower. They do this because deposits are cheaper than other ways to raise money. A bank could issue bonds or borrow from other banks, but those options often cost more than paying interest to depositors. Deposits are also stable: a customer with money in a savings account is likely to keep it there, whereas borrowed money has a fixed repayment date.
Additionally, banks compete for customers. A bank that pays zero interest on savings accounts will lose depositors to competitors who pay even 0.5%. Over time, that loss of deposits shrinks the bank's lending capacity and profit. Paying some interest, even a tiny amount, is cheaper than losing customers.
How deposit insurance affects the interest banks pay
The Federal Deposit Insurance Corporation (FDIC) insures deposits up to $250,000 per account holder per bank. This insurance is free to you but costs banks money. Because your deposits are insured, you face almost no risk of losing money if the bank fails. That safety makes deposits attractive to savers, which means banks do not have to pay as much interest to attract your money as they would if deposits were uninsured.
If deposits were not insured, banks would have to pay much higher interest rates to convince people to take the risk of depositing money. The insurance effectively lowers the cost of deposits to banks, which is one reason deposit rates are lower than rates on riskier investments like bonds or stocks.
The difference between savings accounts, money market accounts, and CDs
Banks pay different interest rates on different deposit products because they have different terms. A savings account lets you withdraw money anytime, so the bank cannot count on having your money for long. A certificate of deposit (CD) locks your money away for a set term—three months, one year, five years—so the bank knows it can lend that money out for the full period. Because the bank has more certainty with a CD, it pays higher interest on CDs than on savings accounts.
A money market account sits between the two: it offers higher interest than a savings account but lower than a CD, and it usually requires a higher minimum balance. The higher rate reflects the fact that you are committing to keep more money in the account, even though you can still withdraw it.
Frequently Asked Questions
Why do some banks pay more interest than others?
Online banks typically pay more because they have lower overhead costs. Banks in competitive markets also pay more to attract deposits. Larger banks may pay less because they have stable customer bases and do not need to compete as hard for new deposits.
Does the interest I earn come from my own money?
No. The interest comes from the fees and interest the bank earns by lending your deposit to other customers. You are not earning a return on your own money; you are earning a share of the bank's profit from lending.
What happens to interest rates if the Federal Reserve cuts rates?
Banks typically lower the interest they pay on deposits within weeks or months. Deposit rates move in the same direction as the Fed's benchmark rate, though not always by the same amount.
Is the interest I earn taxable?
Yes. Interest earned on savings accounts, money market accounts, and CDs is taxable income. Banks send you a 1099-INT form each year reporting the interest you earned, which you report on your tax return.
Can a bank stop paying interest on my account?
A bank can lower the interest rate it pays on your account, but it must notify you in advance. It cannot eliminate interest entirely on most deposit products, though rates can drop to near zero if the Fed's benchmark rate falls.