What Are the Risks of Trading Outside Regular Hours with the 24-Hour Market?
The 24-Hour Market opens up opportunities, but there are risks worth weighing before you use it. The first is liquidity: trading volumes outside Regular Market hours are lower than during the Regular session, which can produce a wider gap between bid and ask prices and make it harder for an order to find a counterparty. The second is volatility: prices tend to move more sharply outside regular hours, particularly when a corporate action is affecting the stock, so a small volume of trading can push a price further than it would during the day. There is also an information gap. Data, news, and events that would normally shape a stock's price during Regular Market hours may not be available while you are trading in an extended session.
- Lower liquidity: trading volumes outside Regular Market hours are lower, so there is potential for a wider bid-ask spread
- Harder to fill: fewer participants means an order may wait longer before finding a counterparty, or not fill at all
- Higher volatility: prices tend to move more sharply outside regular hours, especially where corporate actions affect the stock
- Small volumes move prices further: a modest amount of trading can shift a price more than it would during the Regular session
- Information gap: data, news, and events that normally shape prices during regular hours may not be available in an extended session
- Before you trade: understand these risks and the volatility involved rather than treating the extended sessions as identical to regular hours
Related questions:
Q: What does a wider bid-ask spread actually cost me?
It is the gap between the best available buying and selling price, and a wider gap means you effectively start further from break-even on a position. With fewer participants outside regular hours, that gap can open up noticeably compared with the Regular session, which is one reason a limit price is required in the extended sessions. Set that limit at a level you would genuinely be happy to trade at.
Q: Why are prices more volatile outside regular hours?
Because there is less trading volume to absorb any given order. During Regular Market hours, institutional participation and large volumes tend to keep price moves proportionate. In the extended sessions a comparatively small trade can move a price further, and that effect is amplified when a corporate action is influencing the stock at the same time. The result can look dramatic relative to the same stock during the day.
Q: What is the information gap?
Data, news, and events that would normally inform a stock's price during Regular Market hours may simply not be available while an extended session is running. That means you may be making a decision on a thinner picture than you would have during the day, which is worth factoring in before you commit to a trade. Waiting for the Regular session is a legitimate response to that gap.
Q: How can I manage these risks?
Start by using the limit price the extended sessions require rather than treating it as a formality: set it at a level you would genuinely accept, so a thin market cannot fill you badly. Beyond that, be aware that an order may not fill at all, and consider whether waiting for the Regular session would serve you better. Neither risk disappears simply because the feature is available around the clock.