Endogenous Money Theory

The Textbook Story

Open any introductory economics textbook from the past half-century and you will likely find a section on the money multiplier. The story goes like this. The central bank creates a certain amount of base money (reserves plus currency). Commercial banks receive deposits and are required to hold a fraction as reserves. They lend out the rest, which gets deposited in other banks, which lend out a fraction of that, and so on. Through this multiplier process, an initial injection of base money expands into a much larger total money supply. The central bank, by controlling the monetary base, controls the total quantity of money in the economy.

This model is tidy and intuitive. It is also, according to a growing body of economists, fundamentally wrong.

Loans Create Deposits

Endogenous money theory turns the textbook story on its head. Rather than deposits enabling loans, loans create deposits. When a commercial bank approves a mortgage or a business line of credit, it does not rummage through its vault to find the necessary cash. It credits the borrower’s account with new purchasing power that did not exist a moment before. The loan simultaneously creates an asset (the bank’s claim on the borrower) and a liability (the new deposit in the borrower’s account). Money is not a fixed stock that the central bank doles out; it is a flow that expands and contracts with credit demand.

In this view, the direction of causation is reversed. Banks do not wait passively for deposits to arrive before making loans. They actively seek profitable lending opportunities and create the deposits to fund them. Reserves are obtained after the fact, either from interbank markets or from the central bank, which in practice accommodates the banking system’s demand for reserves to maintain its interest rate target.

Intellectual Roots

The idea that banks create money through lending has a longer history than many people realize. The Swedish economist Knut Wicksell explored the endogeneity of credit in the early twentieth century. Joseph Schumpeter, in his theory of economic development, described bank credit as the creation of new purchasing power rather than the transfer of existing funds.

The modern endogenous money tradition, however, is most closely associated with post-Keynesian economics. Nicholas Kaldor was one of the earliest and most forceful critics of the orthodox money multiplier, arguing in the 1970s and 1980s that the money supply is demand-determined: it expands when credit demand rises and contracts when it falls. The central bank can influence the price of credit (the interest rate) but cannot directly control the quantity.

Basil Moore’s 1988 book Horizontalists and Verticalists gave the theory its sharpest formulation. Moore argued that the money supply curve is horizontal at the central bank’s target interest rate: banks supply whatever quantity of loans the economy demands at that rate. This “horizontalist” position stood in direct opposition to the “verticalist” orthodoxy, which depicted the money supply as a vertical line set by the central bank.

A nuanced middle ground emerged from the work of economists like Marc Lavoie and Louis-Philippe Rochon, sometimes called the “structuralist” position. Structuralists agree that loans create deposits but emphasize that banks face constraints: their own risk assessments, capital adequacy requirements, liquidity preferences, and the willingness of borrowers to take on debt. The money supply is endogenous, but it is not infinitely elastic.

The Bank of England Steps In

For decades, endogenous money theory was a heterodox position dismissed or ignored by mainstream macroeconomics. That changed conspicuously in 2014, when the Bank of England published a quarterly bulletin article titled “Money Creation in the Modern Economy.” The paper stated plainly that “whenever a bank makes a loan, it simultaneously creates a matching deposit in the borrower’s bank account, thereby creating new money.” It described the money multiplier model as a common misconception.

Coming from one of the world’s leading central banks, the statement carried enormous weight. It did not cite Kaldor or Moore by name, but the substance was unmistakably aligned with the post-Keynesian position. The Bundesbank published a similar paper in 2017, and central bank communication has increasingly acknowledged the reality of endogenous money creation.

Implications for Monetary Policy

If money is endogenous, several conventional policy assumptions come under scrutiny.

Quantity control is illusory. Central banks cannot directly control the money supply by adjusting reserves. What they control is the interest rate at which reserves are available. The quantity of money in the economy is then determined by the demand for credit at that interest rate. This is consistent with how central banks actually operate: they announce an interest rate target and supply whatever reserves are needed to maintain it.

The money multiplier is misleading. Empirical studies have repeatedly failed to find a stable relationship between the monetary base and broader measures of the money supply. During quantitative easing programs after 2008, central banks massively expanded reserves, yet broad money growth remained subdued because banks were reluctant to lend and borrowers were reluctant to borrow. The multiplier framework predicted a surge in money supply and potentially inflation; neither materialized on the expected scale.

Credit demand matters. In an endogenous money world, the health of the economy depends critically on whether firms and households want to borrow and whether banks want to lend. A collapse in credit demand, as occurred after the 2008 financial crisis, can lead to a contraction of the money supply regardless of what the central bank does with reserves.

Connection to Modern Monetary Theory

Endogenous money theory is a foundational building block of Modern Monetary Theory (MMT), though the two are not identical. MMT extends the logic of endogenous money to government spending, arguing that a currency-issuing government spends by crediting bank accounts (creating money) and taxes by debiting them (destroying money). Government spending is not financially constrained in the way that household spending is; the real constraint is the productive capacity of the economy and the inflationary consequences of exceeding it.

Not all post-Keynesians endorse MMT’s policy conclusions, but the shared starting point is clear: money is not a scarce commodity that must be collected before it can be spent. It is a social technology created through the institutional apparatus of banking and government.

Why It Matters

Endogenous money theory is more than an academic curiosity. It changes how we think about financial crises (they are credit events, not merely shocks to the “real” economy), banking regulation (capital and liquidity requirements matter more than reserve requirements), and the limits of monetary policy (you can lead a horse to water, but you cannot make it borrow).

Getting the story of money creation right is a prerequisite for getting policy right. The endogenous money framework, once a fringe position, is now increasingly accepted as the more accurate description of how modern monetary systems actually work.