What Is Money Supply?
The plain money supply definition: the stock of currency and bank deposits circulating in an economy at one moment. Not wealth. Not output. Not a pile of cash. Central banks and the IMF measure it as a monetary aggregate, in layers, from currency up through savings and time deposits. We total $144.41T across 159 of the 185 economies we track. Dates run through 2026-06. This page is the starting point. The layers, the mechanism and the country-by-country numbers each have their own deeper page below.
What money supply counts
Two broad ingredients: currency people and businesses actually hold, and deposits sitting at banks. Add up cash outside vaults, checking accounts, savings accounts and short time deposits. That’s most of what any country calls its money supply. The exact mix differs by country. It also differs by how far up the liquidity ladder a given aggregate reaches. That’s the whole reason the layers below exist. What money supply does not count: stocks, bonds, real estate, or anyone’s net worth. A rich country doesn’t always carry a large money supply. A large money supply doesn’t always mean a rich country. The two measure different things.
Who creates it
Commercial banks create most of the money supply, not the central bank. A bank issues a loan and credits the borrower’s deposit account in the same instant. That deposit is new money supply the moment it posts. The Bank of England set the mechanism out in its 2014 Quarterly Bulletin, “Money creation in the modern economy.” A central bank’s own tool is narrower. It can credit bank reserves directly. But reserves aren’t spendable deposits until a bank chooses to lend against them. We cover the full mechanism at money printer go brrr. The deposit-by-deposit detail is at M2 money supply.
The liquidity ladder, in brief
| Layer | Adds | Roughly equals |
|---|---|---|
| M0 monetary base | Physical currency in circulation plus central-bank reserves | The base a central bank creates directly |
| M1 narrow money | Demand deposits, checkable accounts | Money that moves without delay |
| M2 broad money (US label) | Savings deposits, small time deposits under $100,000, retail money market funds | What most rankings mean by “broad money” |
| M3 / M4 | Large institutional deposits, wider near money instruments | Published only in some countries, past broad money |
Every layer sits inside a wider one; nothing skips a rung. The full version of this table lives at the money supply glossary, with the country that reports each letter. The label mapping — M2 here, M3 there, M4 somewhere else — is at broad money.
The layers produce numbers far apart from each other. US broad money is $30.68 trillion (2025-12). The euro area’s is $19.90 trillion (2026-06), reported as M3. China’s is $42.64 trillion (2024), the largest single reading we hold. One concept, three labels, three schedules.
What money supply is NOT
Four things the money supply definition rules out, each one a confusion we see put in writing.
Not wealth. A country can carry a large money supply and modest household net worth, or the reverse. Money supply measures liquid claims, not assets like housing or equities that sit outside it entirely.
Not GDP. One is a stock, measured at a point in time. The other is a flow, measured over a year. A 2019 r/dataisbeautiful commenter asked the honest version of this, after seeing a money-supply-to-GDP chart: “What’s the difference between Hong Kong where BM > GDP, Mexico where BM < GDP, and US/Euro where BM ≈ GDP?” (u/sdweasel, 12 upvotes, 2019-12-19). We hold no GDP data, so we can’t answer that ratio directly. The gap between countries tracks something else. It tracks how much saving flows through bank deposits, rather than through equities, informal savings or foreign accounts. It isn’t how rich or poor a country is.
Not government debt. Government debt is bonds the Treasury owes bondholders. Money supply is currency and deposits held by everyone else. The two do interact. Deficit spending funded through bank-created deposits adds to money supply directly. But they’re different stocks, counted differently.
Not cash. Physical currency in circulation is a thin slice of any money-supply total. Most of it is bank-ledger entries, not paper. In the US, currency plus the non-reserve residual of the monetary base ran near $2.47 trillion (2026-06). That is our own arithmetic, from FRED’s BOGMBASE and TOTRESNS. US broad money stood at $30.68 trillion (2025-12). Cash is the smaller number by an order of magnitude.
One naming point, since it trips people up. Our $30.68T is the IMF’s harmonised broad-money series, not the Fed’s headline M2. The Fed’s own M2 reads about $23T for the same stretch (FRED M2SL). The IMF measure counts more instruments. Two series, two right answers, one label people share.
One r/AskEconomics reply framed why money supply moves the way it does, using a mortgage payment as the example. Paying down a loan is “a simultaneous write-down of my deposit asset and mortgage liability” (u/dtr9, 2 upvotes, r/AskEconomics, 2024-10-26). Money isn’t spent away — it’s unwound. Money supply grows when new loans post. It shrinks when old ones get repaid. Neither move is really about a printing press.
Where to go next
Every term above links to its own page. The base is at monetary base; the cross-country concept is at broad money; the US definition specifically is at M2 money supply. The full 185-economy dataset and the world total turn every definition here into a ranked number. The methodology page states exactly which 24 economies we can’t convert to dollars, and why.
FAQ
What is the monetary base vs. the money supply?
The monetary base (M0) is currency plus the reserves banks hold at the central bank — the layer a central bank creates directly. Money supply is wider and mostly bank-created: loans generate deposits, and those deposits are new money supply the instant they post. See monetary base for the 2008–2014 case where the two diverged sharply.
Is M2 the same as money supply?
M2 is the United States’ specific name for its own broad-money aggregate. “Money supply” is the general term; M2, M3 and M4 are national labels different countries put on their own version of it. See broad money for the full country-by-country mapping.
Why do economists track M2?
It’s the broadest US aggregate the Federal Reserve still publishes and updates monthly. Its growth rate has historically tracked with inflation over multi-year horizons, if not month to month. It’s the number behind every “is the Fed printing money” argument. See M2 money supply for what actually drives it up.
What is the Federal Reserve definition of money supply?
The Federal Reserve definition covers currency, checking deposits, savings deposits, small time deposits and retail money market funds — the components inside M2, its own broad-money aggregate. That’s a US-specific money supply definition; other countries define their own headline aggregate differently. See broad money for the country-by-country version.
How is money supply calculated?
Central banks add up reported currency and deposit balances directly; there’s no formula and no estimate in the raw total. Growth rates — year over year, 10-year CAGR, doubling time — are the only figures computed afterward, and we compute all three ourselves for every economy we track.