What is Illiquid? (Plain English Definition)
Definition: An illiquid investment is one that cannot be easily bought or sold without significantly affecting its price, often due to low trading volume.
Illiquid Explained Simply
An illiquid asset is one that is difficult to sell quickly at a fair price. Illiquidity can stem from low trading volume, a limited number of buyers and sellers, or the nature of the asset itself. Real estate, art, and private equity are examples of inherently illiquid assets. In the ETF world, illiquidity typically manifests as wide bid-ask spreads and low daily trading volume.
An ETF can be illiquid for several reasons. It might be a new or niche fund with few investors. It might hold illiquid underlying assets like small-cap stocks, emerging market bonds, or real estate securities. During market crises, even normally liquid ETFs can become temporarily illiquid as sellers overwhelm buyers.
Illiquidity imposes real costs on investors. Wide bid-ask spreads mean you pay more when buying and receive less when selling. In extreme cases, you might not be able to sell at any reasonable price during a market panic. Large orders in illiquid ETFs can also move the price against you, a problem called market impact.
Illiquid Example
A popular S&P 500 ETF like SPY trades over 80 million shares per day with a bid-ask spread of just $0.01. A niche thematic ETF might trade only 10,000 shares per day with a spread of $0.15. If you need to sell $100,000 of each during a market downturn, you can exit SPY instantly at near-fair value. But selling $100,000 of the niche ETF (about 2,000 shares) could take multiple days and cost you $300 or more in spread costs alone.
Why Illiquid Matters for ETF Investors
Illiquidity risk is often overlooked by ETF investors until they need to sell during a stressful market environment. The ease of buying an ETF online can mask the difficulty of selling it during a crisis. This is especially true for niche, thematic, and international bond ETFs. For ETF investors, sticking with liquid, well-established funds for core portfolio positions is a prudent approach. Check daily trading volume and the bid-ask spread before investing. As a general rule, ETFs with less than $50 million in AUM or fewer than 50,000 shares traded daily may present liquidity challenges, especially during volatile markets.
Illiquid vs Liquidity
| Illiquid | Liquidity |
|---|---|
| An illiquid investment is one that cannot be easily bought or sold without significantly affecting its price, often due to low trading volume. | See full definition of Liquidity |
While illiquid and liquidity are related concepts, they serve different purposes in the world of ETF investing. Understanding both terms helps you make more informed decisions about which funds to include in your portfolio and how to evaluate their performance.
Related Terms
Deepen your understanding of ETF investing by exploring these related concepts:
Liquidity
Liquidity refers to how quickly and easily an investment can be bought or sold without significantly affecting its price.
Bid-Ask Spread
The bid-ask spread is the difference between the highest price a buyer will pay and the lowest price a seller will accept for a security.
Assets Under Management (AUM)
Assets under management (AUM) is the total market value of all investments held within a fund, representing its overall size.
Trading Volume
Trading volume is the total number of shares of a security that are bought and sold during a specific time period, usually one day.
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