A bank is a business that holds your money, lends it out, and charges fees for those services

A bank is a licensed financial institution that takes deposits from customers, keeps that money safe, and lends portions of it to other customers or businesses. In return, the bank pays you a small amount of interest on your deposit and charges borrowers a higher interest rate on loans. The difference between what they pay you and what they charge borrowers is how banks make money. Banks also charge monthly fees, overdraft fees, and fees for specific services like wire transfers or cashier's checks.

When you put money into a bank account, you are not handing the bank your cash to lock in a vault with your name on it. You are lending the bank your money. The bank then uses that money to make loans to other customers, invest it, or hold it in reserve. Your account balance is a record of how much the bank owes you, not a pile of your actual bills sitting somewhere. The bank is required by law to give you that money back on demand—that is what makes it a deposit account rather than an investment.

Banking is the business of managing these deposits and loans at scale. A bank's job is to move money between people who have it and people who need it, while staying profitable and following strict government rules about how much money they must keep on hand and how they can use customer deposits.

Key Takeaways

  • Banks accept deposits, pay you interest on them, and lend that money to other customers at a higher rate—the difference is their profit.
  • Your bank account balance represents money the bank owes you, not physical cash stored under your name.
  • Banks are regulated by federal and state agencies that set rules about reserves, lending practices, and consumer protections.
  • Banks make money through interest on loans, monthly account fees, overdraft fees, and charges for specific services.
  • When a bank fails, the Federal Deposit Insurance Corporation (FDIC) protects deposits up to $250,000 per account holder per bank.

How banks use your deposits

When you deposit money into a checking or savings account, the bank when ready has the legal right to use that money. They lend it to mortgage borrowers, car buyers, small business owners, and other customers. They also invest it in government bonds and other securities. The bank keeps a percentage of deposits in reserve—the amount varies by account type and is set by the Federal Reserve—so they can always pay you if you withdraw your money.

This is why banks can afford to pay you interest on savings accounts: they are earning more interest on the loans they make with your money than they pay you. A bank might pay you 0.01% annual interest on a savings account while charging a mortgage borrower 6% or 7%. That spread is their primary source of income. The bank also keeps a portion of deposits as a safety buffer and invests some in low-risk securities.

You are protected in this arrangement by federal law. The bank cannot lend out 100% of deposits or take excessive risks with your money. If a bank fails, the FDIC insures deposits up to $250,000 per depositor per bank, so you do not lose your money even if the institution collapses.

Types of banks and what they do differently

Not all banks operate the same way. A commercial bank (also called a retail bank) is what most people use—it offers checking accounts, savings accounts, personal loans, and mortgages to individuals and small businesses. A credit union is a member-owned nonprofit that works similarly but is run by and for its members rather than shareholders; credit unions often charge lower fees and pay higher interest on savings, though membership is usually restricted to people who work in a certain industry or live in a certain area.

An investment bank does not take deposits from regular customers. Instead, it helps large companies and wealthy individuals buy and sell stocks, bonds, and other securities, and it advises on mergers and acquisitions. A savings bank or thrift traditionally focused on mortgages and savings accounts but now operates much like a commercial bank. Online banks have no physical branches and typically offer lower fees and higher interest rates because they have lower overhead costs.

All of these institutions are regulated, but the rules differ. Commercial banks and credit unions are regulated by the Federal Reserve, the FDIC, and state banking authorities. Investment banks face different rules from the Securities and Exchange Commission (SEC). The type of bank you choose affects the fees you pay, the interest you earn, and the services available to you.

What regulators require banks to do

Banks operate under strict rules set by federal and state governments. The Federal Reserve sets interest rates and requires banks to hold a minimum amount of capital (money they own, not deposits) so they can absorb losses without failing. The FDIC insures deposits and examines banks to make sure they are not taking excessive risks. The Office of the Comptroller of the Currency (OCC) charters and regulates national banks. State banking authorities regulate state-chartered banks.

Banks must also follow Know Your Customer (KYC) rules, which require them to verify who you are when you open an account and monitor accounts for suspicious activity. They must report large cash deposits (over $10,000) and suspicious transactions to the Financial Crimes Enforcement Network (FinCEN). These rules exist to prevent money laundering and terrorist financing, not to spy on you—but they do mean banks collect information about you and can freeze or close your account if activity looks unusual.

Banks must also disclose their fees, interest rates, and terms clearly before you open an account. They cannot charge you overdraft fees without your permission, and they must notify you before charging overdraft fees on debit card transactions. These consumer protection rules are enforced by the Consumer Financial Protection Bureau (CFPB).

How banks make money beyond interest

Interest on loans is the largest source of bank revenue, but it is not the only one. Banks charge monthly maintenance fees (typically $5 to $15) for keeping an account open, though many waive these if you maintain a minimum balance or set up direct deposit. They charge overdraft fees (usually $25 to $35 per transaction) when you spend more than your balance, and some charge a daily fee if your account stays negative. They charge NSF fees (non-sufficient funds) when a check bounces.

Banks also charge for specific services: wire transfers ($15 to $30), cashier's checks ($5 to $15), stop-payment orders ($25 to $35), and expedited card replacement ($15 to $25). Some charge fees to speak with a teller or to use another bank's ATM. Credit card companies (which are often owned by banks) make money from interest on balances and from fees merchants pay when you swipe your card—typically 2% to 3% of the transaction amount.

These fees add up. A person who overdrafts once a month and pays a $35 fee is paying $420 a year just for that one mistake. A person who uses out-of-network ATMs three times a month at $3 per transaction pays $108 a year. Banks rely on these fees, especially from customers who do not maintain high balances or who frequently overdraft.

What happens when a bank fails

Bank failures are rare in the United States because of regulation and deposit insurance, but they do happen. When a bank fails, the FDIC steps in. If you have deposits under $250,000 at that bank, you are paid in full. If you have more than $250,000, the amount over $250,000 is at risk—you may recover some of it if the bank's assets are sold, but there is no may provide.

The FDIC limit applies per depositor per bank. If you have $200,000 in a checking account and $100,000 in a savings account at the same bank, you are covered for the full $300,000 because both accounts are in your name at the same institution. If you have $200,000 at Bank A and $200,000 at Bank B, both are fully covered because they are at different banks. If you have a joint account with your spouse, each of you is insured for up to $250,000 in that account, so a joint account with $500,000 is fully covered.

When a bank fails, the FDIC typically arranges for another bank to buy it, and your account transfers seamlessly. You keep your account number, your debit card works, and your money is still there. The process is usually invisible to you. In rare cases where no bank buys the failed bank, the FDIC pays you directly, usually within a few days.

The difference between banks and other financial institutions

A bank is not the same as a brokerage, an insurance company, or a money transmitter, though some large financial companies own all of these. A brokerage (like Fidelity or Charles Schwab) buys and sells stocks and bonds for you; it does not take deposits or make loans. An insurance company sells insurance policies; it does not hold your money in an account. A money transmitter (like Western Union or PayPal) moves money between people but does not take deposits or make loans.

Some of these institutions offer services that look like banking—PayPal has a cash balance, for example—but they are not banks and are not regulated the same way. Your money in a PayPal account is not FDIC-insured the way a bank deposit is. Money transmitters are regulated by state authorities and the Financial Crimes Enforcement Network, but they face different rules than banks.

This matters when something goes wrong. If a bank fails, the FDIC protects you. If a brokerage fails, the Securities Investor Protection Corporation (SIPC) protects you, but only up to $500,000 per account and only for securities and cash held for investment—not for cash sitting in a money market account. If a money transmitter fails, you may have no protection at all, depending on the state and the company's practices.

Frequently Asked Questions

Is my money actually safe in a bank?

Your money is safe up to $250,000 per account type per bank because of FDIC insurance. Banks are also required to keep a percentage of deposits in reserve and cannot lend out 100% of what customers deposit. If you have more than $250,000, spread it across multiple banks or account types to stay within the insurance limit. Banks fail rarely because of regulation, but when they do, the FDIC steps in.

Why do banks charge so many fees?

Banks charge fees because they make less money on interest when rates are low and because fees are predictable revenue. A $35 overdraft fee is more profitable than the interest earned on a small account balance. Banks also charge for services that cost them money to provide, like processing wire transfers or issuing cashier's checks. You can avoid most fees by maintaining a minimum balance, using your bank's ATMs, and not overdrafting.

What is the difference between a bank and a credit union?

A credit union is a nonprofit owned by its members, while a bank is a for-profit business owned by shareholders. Credit unions often charge lower fees and pay higher interest because they do not need to generate profit for owners. However, credit union membership is usually restricted—you might need to work in a certain industry or live in a certain area. Both are insured by the FDIC or the National Credit Union Administration (NCUA) up to $250,000.

Can a bank take my money without permission?

A bank can freeze your account or close it if it suspects fraud or illegal activity, but it cannot straightforward take your money. If you owe the bank money (like an unpaid loan or credit card debt), the bank can use a process called offset to take money from your account to pay what you owe, but this must follow legal procedures. If you believe a bank has wrongly taken your money, you can file a complaint with the CFPB or your state banking authority.

What happens to my money if I do not use my account for a long time?

Your money does not disappear, but if you do not use your account for a long period (usually three to five years, depending on the state), the bank may declare it dormant and turn the money over to the state as unclaimed property. You can still claim it by contacting your state's unclaimed property office, usually through a website like MissingMoney.com. The money is yours; the state just holds it until you ask for it back.