Topics Money and economics

How do banks make money?

Banks make money mainly by charging more interest on loans than they pay on deposits. When you put money in a savings account, the bank pays you a small rate. It then lends that money out, as mortgages, car loans, business loans and credit card balances, at higher rates. The difference is called the net interest margin, and for most traditional banks it is the largest source of income.

What makes it interesting is how much else is layered on top. Banks charge fees for accounts, overdrafts, wire transfers and cards. Every time you swipe a debit or credit card, a small fee called interchange is split among the businesses in the chain. Larger banks also advise on mergers, help companies sell stock and bonds, manage investments for clients, and trade. Banks also keep only a fraction of deposits on hand, which is why rules about capital and reserves matter so much.

An episode would walk through all of this with one simple example: a deposit coming in, a loan going out, and the money earned and risked in between. It would also cover what happens when borrowers do not repay. bre is an app whose hosts are AI, so they can be wrong, and the episode is an explanation of how banking works, not financial advice.

What a bre episode would cover

An outline of the episode bre would make for this question. Every episode is written fresh when you ask, so yours will differ.

  1. The gap between saving and borrowingHow a bank pays a little interest on deposits and charges more on loans, and why that spread is the core of the business.
  2. Where your deposit actually goesWhy a bank does not keep your cash in a vault, how fractional reserve banking works, and what it means for risk.
  3. Fees, cards and everyday chargesAccount fees, overdraft charges and card interchange: the smaller streams that add up across millions of customers.
  4. Investment banking and wealth managementHow big banks earn from advising companies, underwriting stocks and bonds, trading, and managing money for clients.
  5. When loans go badWhy banks set aside money for defaults, how they judge borrowers, and what losses do to profits.
  6. Why interest rates change the pictureHow central bank rate moves can widen or squeeze a bank's margin, and why that is not always simple.
  7. Rules that keep banks standingA look at capital requirements and deposit insurance, and why regulators watch banks closely.

How the episode might open

A sample exchange between two of bre’s AI hosts, bre and Arlo. Both are AI; this is written by AI, as every bre episode is.

  1. breAI host

    Okay, so you hand a bank your paycheck and it gives you a debit card and a tiny bit of interest. That feels like a bad deal for the bank. How does it make money?

  2. ArloAI host

    It lends your money out. Higher rate. Pockets the gap.

  3. breAI host

    Right, that's the heart of it. You get, say, a small rate on savings, and someone else pays a much bigger rate on a car loan. The bank lives in the middle.

  4. ArloAI host

    So it's a middleman. With your cash.

  5. breAI host

    Kind of, yes. But here's where it gets odd: the bank doesn't keep your money sitting there waiting. Most of it is out working somewhere.

  6. ArloAI host

    Then what if you want it back? Who counted that?

  7. breAI host

    Good question, and it's the reason banks have rules about how much cash and capital they hold. Most people don't all ask on the same day.

  8. ArloAI host

    Most people. Not all.

  9. breAI host

    Which is exactly the risk we'll dig into. Let's start with one deposit and follow it.

Questions people also ask

What is a bank's main source of income?
For most traditional banks, it is net interest income: the interest earned on loans and other assets minus the interest paid on deposits and borrowing. Fees and other services matter too, and big banks also earn from investment banking, trading and wealth management.
Do banks use my deposits to make loans?
Yes, in effect. Banks lend out a large part of what customers deposit and keep a portion as reserves and capital. Deposits at insured banks are protected up to a limit by government insurance in the United States, which helps keep people confident.
Why do banks charge fees if they earn interest?
Interest income can rise and fall with rates and loan demand, while fees are steadier. Fees also pay for services such as accounts, transfers and card processing. Some fees, like overdraft charges, are debated, and rules about them have changed over time.
How do banks make money when interest rates change?
It depends on the bank. Higher rates can let banks charge more on loans, but they may also have to pay more to depositors, and borrowers may default more often. Lower rates can squeeze margins. The overall effect is not the same for every bank.

Related topics

More: all 300 topics, money and economics, or the longer reads on /learn.

bre’s hosts are AI, and every episode is generated, so they can be wrong: check anything that matters. This page outlines what an episode would cover. It is for interest and learning, not medical, financial or legal advice.