A bank holds your money, moves it where you tell it to go, and lends it out to make profit
A bank is a business that takes deposits from customers, keeps that money safe in a vault or electronic ledger, and uses it to make loans to other customers and businesses. When you put money in a checking or savings account, the bank now owns that money legally — you own the right to withdraw it. The bank pays you a small amount of interest (or nothing, depending on the account) and lends your money to someone else at a higher interest rate. The difference between what they pay you and what they charge borrowers is how they make money.
The core purpose is threefold: safekeeping, movement, and lending. You need somewhere secure to store cash that won't burn down or get stolen. You need a way to pay people without carrying physical bills — a check, a debit card, an electronic transfer. And the bank needs to turn a profit, which it does by borrowing your deposits cheaply and lending them out expensively.
Key Takeaways
- Banks hold your deposits in accounts and pay you interest (usually very small) in exchange for the right to lend that money to others.
- A bank makes money by charging borrowers a higher interest rate than it pays you, and by collecting fees on accounts and services.
- Your deposits are insured by the FDIC up to $250,000 per account type per bank, so your money is protected even if the bank fails.
- Banks move money between accounts, process payments, and provide credit — services that cost them money to operate, which is why they charge fees.
- Not all financial institutions are banks; credit unions, investment firms, and payment apps work differently and have different rules.
How a bank makes money from your deposits
When you deposit $1,000 in a savings account, the bank does not lock that money in a box with your name on it. It adds $1,000 to its pool of deposits and lends $900 of it to someone buying a car at 6% interest. You might earn 0.01% interest on your $1,000 — about 10 cents a year. The car buyer pays the bank $54 a year in interest. The bank keeps the $44 difference, minus the cost of running the branch, paying staff, and processing the loan.
This is called the interest rate spread, and it is the primary way banks profit. The larger the gap between what they pay depositors and what they charge borrowers, the more money they make. During periods when the Federal Reserve keeps interest rates low, banks earn less on deposits but can still charge high rates to borrowers — which is why savings accounts often pay almost nothing.
Banks also make money from fees: overdraft fees when you spend more than you have, monthly maintenance fees on checking accounts, ATM fees when you use another bank's machine, wire transfer fees, and late fees on loans. Some accounts waive these fees if you maintain a minimum balance or set up direct deposit.
Why banks need to hold reserves and follow rules
A bank cannot lend out every dollar it receives. Federal regulators require banks to keep a percentage of deposits on hand as reserves — money that must stay in the vault or at the Federal Reserve, not lent out. This protects you: if many customers try to withdraw money at once, the bank has cash available. The reserve requirement varies depending on the type of account and the bank's size, but it is typically between 0% and 10%.
Banks are also required to follow strict rules about who they lend to, how much they can lend relative to their capital, and how they report their finances. The FDIC (Federal Deposit Insurance Corporation) insures deposits up to $250,000 per account type per bank. If a bank fails, the FDIC pays depositors from an insurance fund, not from taxpayer money directly — though the FDIC is a government agency.
These rules exist because banks are not just businesses; they are the backbone of the payment system. If a major bank fails, it can disrupt the entire economy. The 2008 financial crisis happened partly because banks made risky loans and regulators did not catch it in time.
What banks do beyond holding money
Modern banks offer services beyond deposits and loans. They process ACH transfers (electronic payments between bank accounts), issue debit cards that let you spend money directly from your account, and provide wire transfers for moving large sums quickly. They also offer credit cards, mortgages, investment accounts, and safe deposit boxes.
Each service has a cost to operate. Processing a wire transfer requires staff, technology, and compliance with anti-money-laundering rules. Issuing a debit card means the bank pays Visa or Mastercard a small percentage of each transaction. These costs are why banks charge fees, and why free checking accounts often come with strings attached — like requiring direct deposit or maintaining a minimum balance.
The difference between banks and other financial institutions
Credit unions are member-owned cooperatives that work similarly to banks but are not for-profit. They typically offer lower fees and higher savings rates because they do not need to generate profit for shareholders. However, they are smaller and may have fewer branches or services.
Investment firms like Fidelity or Vanguard hold money but do not take deposits the way banks do. They manage investments and charge fees based on assets under management. Your money is not FDIC-insured because it is invested in stocks or bonds, not held as a deposit.
Payment apps like Venmo, PayPal, and Cash App move money between users but do not hold deposits in the traditional sense. Some partner with banks to offer FDIC-insured accounts, but others hold your balance in a non-bank account that has different protections.
What happens when you need money back
When you withdraw cash from an ATM or write a check, the bank deducts that amount from your account balance. If you withdraw more than you have, most banks will either decline the transaction or charge you an overdraft fee and cover the difference as a short-term loan. Some banks offer overdraft protection, which links your checking account to a savings account or credit line so transfers happen automatically instead of triggering a fee.
If you close your account, the bank returns all your money (minus any outstanding fees or holds). If the bank fails, the FDIC steps in and either transfers your account to another bank or sends you a check for up to $250,000. This process usually takes a few days.
Why banks charge different rates to different people
A bank charges you 0.01% on savings but charges a borrower 6% on a car loan because the borrower is riskier. The bank runs a credit check, looks at income and employment history, and assesses the likelihood that the borrower will default. A person with a high credit score and stable income gets a lower rate. Someone with missed payments or no credit history pays more — or gets denied entirely.
This is also why savings rates vary. During periods when the Federal Reserve raises interest rates, banks compete for deposits by offering higher rates. When rates fall, banks lower what they pay depositors because they do not need to attract deposits as aggressively.
Frequently Asked Questions
Can a bank take my money if it goes bankrupt?
No. The FDIC insures deposits up to $250,000 per account type per bank. If the bank fails, the FDIC pays you directly or transfers your account to another bank. You will have access to your money within a few business days. Amounts over $250,000 are at risk, which is why some people split large balances across multiple banks.
Why do banks pay almost no interest on savings accounts?
Banks pay low rates because they can borrow your money cheaply. When the Federal Reserve keeps interest rates low, banks have little incentive to compete for deposits by offering higher rates. If rates rise, savings rates usually follow within a few months. High-yield savings accounts at online banks often pay more because they have lower operating costs than brick-and-mortar branches.
What is the difference between a debit card and a credit card?
A debit card spends money you already have in your bank account. A credit card borrows money from the card issuer, which you repay later with interest. Banks issue both, but they work differently: debit is immediate and has no debt; credit builds a balance you owe.
Do I need a bank account to receive a paycheck?
No, but most employers require direct deposit into a bank or credit union account. If you do not have an account, you can cash a paper check at the issuing bank (usually free) or at a check-cashing service (which charges a fee). Some employers still issue paper checks if you request it, but this is becoming less common.
What happens to my money if I do not use my account for years?
Your money stays in the account. However, if you do not make any deposits or withdrawals for a long period (typically three to five years, depending on state law), the account may be declared dormant and transferred to your state's unclaimed property program. You can still recover it by contacting your state's treasurer office, but you will need to prove ownership.