Liquidity

What Is Liquidity?

Liquidity describes how easily something can be turned into cash. In financial markets, it usually refers to how quickly a security, such as a stock or bond, can be bought or sold without causing a large change in its price. A highly liquid asset has many buyers and sellers actively trading it, so an order can usually be filled almost immediately at a price close to the most recent quoted level. An illiquid asset may take longer to sell, or may only sell at a noticeable discount.

Liquidity also applies to the wider economy and to individuals. A business with plenty of cash on hand or easily sold assets is considered liquid, while a household whose wealth is mostly tied up in a house has less liquidity.

How Liquidity Is Measured

Investors often look at a few indicators when judging a market's liquidity:

• Bid-ask spread: the gap between the highest price a buyer will pay and the lowest price a seller will accept. Narrow spreads generally signal higher liquidity.
• Trading volume: the number of shares or contracts traded over a given period. Higher volume usually means more active trading.
• Market depth: the quantity of buy and sell orders waiting at different price levels. Deep markets can absorb large orders with little price impact.

Why It Matters to Investors

Liquidity affects both the cost and the flexibility of investing. In a liquid market, transaction costs tend to be lower and an investor can enter or exit a position when needed. In an illiquid market, selling a large holding may push the price down, and during periods of stress, buyers can become scarce altogether. This risk is sometimes called liquidity risk.

Liquidity also varies over time. Major news events, market crashes, or sudden shifts in investor sentiment can cause liquidity to dry up quickly, even in markets that normally trade actively. Investors who hold less liquid assets, such as certain small-company shares, thinly traded bonds, or private investments, may face longer waiting periods or greater price uncertainty when they want to sell.

Example

Consider two stocks. A large, widely held company may trade millions of shares per day with a spread of a cent or two. A small, thinly traded company may trade only a few thousand shares daily with a wider spread. Selling a modest number of shares in the first case is typically straightforward, while selling the same number in the second may take time or require accepting a lower price.