Why Banks Don't Actually Need Your Deposits to Make Loans

How It Works

The intuitive model of banking — savers deposit money, the bank lends that same money to borrowers — is how virtually everyone imagines the system works. It is also wrong, and not according to critics: the Bank of England said it plainly in a landmark 2014 paper: 'Whenever a bank makes a loan, it simultaneously creates a matching deposit in the borrower's bank account, thereby creating new money.'

Here is what actually happens. When a bank approves your $300,000 mortgage, it does not check the vault or round up other customers' savings. It types $300,000 into your account. On its balance sheet, it records a new asset (your loan, which will earn interest for 30 years) and a new liability (your deposit) in the same instant. Money that did not exist a moment ago now exists. This is the engine at the heart of fractional reserve banking — described in detail in how banks create money out of thin air.

So what constrains lending, if not deposits? Three things. Capital requirements: regulators require banks to hold shareholder capital proportional to their risk-weighted loans, so a bank can only lend a multiple of its equity cushion. Profitability: every loan must be funded, and funding costs money — the bank needs the loan's interest rate to exceed its funding cost. And demand: banks need creditworthy borrowers willing to pay the prevailing interest rate.

This is where your deposits re-enter the story. When the borrower spends that new $300,000, most of it flows to accounts at other banks, and the lending bank must settle up with reserves. It can obtain those reserves by borrowing from other banks, issuing bonds, or borrowing from the Fed — but all of those cost roughly the market interest rate. Customer deposits, paying 0.1%, are by far the cheapest funding available. Banks don't need *your* deposit to make the loan — they need deposits generally, afterward, because deposits are the cheapest way to fund the balance sheet they've created.

Why It Matters

This distinction sounds academic but changes everything about how you read the financial system. It explains why the money supply expands in booms and contracts in busts — lending, not saving, drives money creation, which is where most money actually comes from. It explains why the Fed manages the economy through interest rates rather than by rationing some fixed pool of loanable funds. And it explains why banks fight so hard to keep your deposits while paying you almost nothing: they aren't competing for lending fuel, they're competing for the cheapest funding on earth.

It also reframes the stablecoin fight. Banks argue that if deposits migrate to yield-bearing digital dollars, they 'won't be able to lend to communities.' But since loans create deposits rather than the reverse, deposit flight doesn't mechanically destroy lending capacity — it raises banks' funding costs and squeezes their margins. That is a real business problem for banks, but it is a profitability argument dressed up as a public-interest one — the same pattern found in why banks are fighting stablecoin yield.

Real-World Example

Follow one mortgage through the system. Monday: a bank approves a $300,000 home loan and credits the borrower's account — $300,000 of new money exists. Tuesday: the borrower wires it to the home seller, whose account is at a different bank. The lending bank now owes that other bank $300,000 in reserves. It settles using its reserve balance, then replenishes by attracting deposits (paying ~0.1%), borrowing overnight from other banks (~5% when rates are high), or issuing bonds (~5.5%). The loan happened first; the scramble for funding happened after. Multiply this by millions of loans, and you see why banks blanket the country with 'free checking' offers: every low-cost deposit they capture replaces expensive market funding, and the spread is their profit.