23-Hour Stock Trading: Does More Trading Make Better Investors?

December 6th could mark a turning point in the way markets work. Trading already resembles a virtual casino, with prediction markets, one-day options, and a constant stream of social media advice on everything imaginable. Accountability for that advice, and for the accuracy of the claims behind it, is largely missing. Now the New York Stock Exchange has no intention of being left out.

 

What began with 24 brokers under a buttonwood tree in New York City on May 17, 1792, has grown into an exchange with a trading day that has run from 9:30 a.m. to 4:00 p.m. for decades. That familiar schedule is about to change.

 

Beginning December 6, the NYSE will extend trading to 23 hours a day, five days a week. That leaves one hour, from 8:00 p.m. to 9:00 p.m., to sleep, eat, or attend to whatever else life requires. The market will offer more time to trade. But is that good for investors?

 

 

The Risks of 23-Hour Stock Trading

The argument in favor of the switch is that institutional investors have long been able to trade outside normal market hours, so it is time to give the rest of us the same access. But has that privilege improved their results? Their performance does not appear to have gotten any better.

The Wall Street Journal reported that MIT’s endowment earned half the S&P 500’s return for the year ended June 30, 2026. MIT has access to the largest investment firms and alternative investments with minimum commitments well beyond the reach of most individual investors. Access, however, is not the same as an advantage.

Moving to 23-hour trading seems to take us further down the road of speculation. The NYSE has acknowledged that trading volume will be much lighter during overnight hours, which isn’t surprising if not obvious.

The concern is what happens when a recession-related headline or major geopolitical event breaks at 10 p.m. on a Monday. With fewer investors participating, the market could swing sharply in either direction, while momentum traders amplify the move.

Is extended trading entirely bad? Not necessarily. But giving people more hours to trade doesn’t necessarily make markets better for investing.

Fundamentals Matter More Than Trading Hours

When you focus on long-term cash flow growth, a Monday market move matters far less and may even create an opportunity. Knowing what you’re willing to pay for a business, and why, can turn volatility to your advantage. Sharp price swings can be short-lived, so the prepared investor is better positioned to act when opportunity appears.

Trading and investing are two different disciplines. The mindset of a trader looks forward to the 23-hour change, with more opportunities to buy and sell. An investor who owns a company’s stock for several years won’t remember if it was bought at 10 am or 10 pm. What will matter is how the business performed.

For the long-term investor, more trading hours may mean more distractions.

Observations on the Market No. 424