What is market liquidity?

What does market liquidity mean?

The SEC's Investor.gov defines liquidity as how easily or quickly a security can be bought or sold in a secondary market. FINRA adds the part that matters most for your wallet: in a liquid market, participants can buy and sell without significantly affecting prices.

So liquidity is not just whether a trade is possible. It is what the trade costs. FINRA contrasts stocks, whose orders are matched electronically on exchanges, with bonds, most of which trade through dealer networks and many only occasionally. A rarely traded bond, a small company's stock or a newly launched token may have a quoted price but very few buyers or sellers standing behind it.

This page is about market liquidity — trading an asset. The word is also used in other senses, such as whether a firm can raise cash or borrow.

How do professionals measure liquidity?

A 1999 report by the Committee on the Global Financial System, hosted by the Bank for International Settlements, set out three dimensions that are still widely used:

The same report mentions immediacy — how long it takes to execute a trade of a given size within a given price range — which combines all three. A market can look tight (a small spread) yet be shallow (little size behind that spread). That is when big orders get expensive.

What happens when you trade in a thin market?

On an exchange, buy and sell orders queue in an order book at different prices. A market order takes the best available prices first, then moves to worse ones if the first level runs out. Traders call this walking the book; the gap between the price you expected and the price you got is slippage.

1. Check the spread as a percentage of the price before you trade.

2. Check the depth: how much is offered at or near the best price compared with your order size?

3. Use a limit order to cap the price you pay or accept, accepting that it may not fill.

4. Split large orders or trade when activity is higher, if the venue allows.

Why does liquidity disappear in a crisis?

Liquidity depends on someone being willing to take the other side. Under stress, many investors want to sell at once while dealers and other buyers step back, so spreads widen and depth thins. FINRA notes that most bonds trade through dealer networks rather than on exchanges, and that liquidity can drop during market stress, sector credit scares or when dealers have little inventory.

March 2020 was a clear case. A report by the SEC's economists described a rush for cash as the COVID-19 shock hit: bid-ask spreads in the US Treasury market spiked to historical levels, and corporate bond spreads widened by as much as 100 basis points for high-yield and 150–200 for investment-grade bonds. Spreads then fell rapidly after the Federal Reserve announced facilities to support corporate credit. The Fed's own May 2020 review said Treasury market functioning had become unusually strained before returning to more typical levels.

How liquid are crypto markets?

The largest crypto-assets trade around the clock on many platforms, which can make them look highly liquid. The ECB has flagged reasons for caution: prices for the same asset differ across platforms, data providers aggregate them in different ways, and wash trading — trades that create volume without a real change of ownership — has distorted reported figures. Smaller tokens may have very little depth at all.

Liquidity in decentralized exchanges works differently, through pools of tokens rather than order books; see decentralized exchanges and AMMs. And a token's market cap tells you nothing about how much of it could actually be sold; see market capitalization explained.

What mistakes do people make with liquidity?

• Trusting the last price. It is what someone paid for a small amount, not what you will get for a large one.
• Using market orders in thin markets. You may walk the book and pay far more than the screen suggested.
• Treating reported volume as real depth. In crypto especially, volume can be inflated.
• Assuming you can always exit. In March 2020 even Treasury markets were strained. Plan for needing cash when markets are stressed.
• Ignoring the bond dealer's spread. FINRA suggests asking how often a bond has traded recently before buying it.