Some capital markets organizations have moved to round-the-clock (or nearly so) trading, and a recent announcement from the New York Stock Exchange indicates a broader shift in this direction could be on the way.

The NYSE in October said it plans to extend trading to 22 hours a day on its Arca exchange, the top U.S. exchange for listing and trading exchange-traded funds, which are among the most popular financial instruments for investors. Intercontinental Exchange Group, the owner of NYSE Arca, filed a rule change with the U.S. Securities and Exchange Commission to allow Arca to be open from 1:30 a.m. to 11:30 p.m. ET, beyond its current extended trading hours of 4 a.m. to 8 p.m. ET.

Given President Trump’s recent regulatory freeze and the need for Trump-appointed agency heads to review the change, SEC approval may be delayed. Ultimately, though, approval is anticipated, as the Trump administration is likely to emphasize a more pro-business climate for exchanges, broker-dealers and clearinghouses.

Further demonstrating the shift toward near-24-hour markets, the 24X National Exchange has already received SEC approval to offer U.S. equities trading 23 hours a day, five days a week. The exchange plans to launch in the second half of 2025.

The change would give investors and traders more on-demand access in the stock market and trading space, where regular trading hours of 9:30 a.m. to 4 p.m. ET, Monday through Friday, have been unchanged since 1985. Some broker-dealers already offer all-day trading via alternative trading systems, like Blue Ocean ATS. Currently, 30 to 40 million shares are traded on the Blue Ocean ATS platform each night, showing the growing demand for overnight trading.

Once the NYSE adjusts its trading hours to close to 24 hours, other capital markets players, including essential functions of Wall Street, such as clearinghouses, are expected to follow suit. The National Securities Clearing Corporation, which guarantees completion for virtually all equity transactions, is already discussing the move to near-continuous operation.

Labor implications

One major implication of shifting toward round-the-clock trading involves the labor force that supports our markets—specifically traders, whose jobs are already notorious for being fast-paced and demanding. With the markets open nearly 24 hours a day, they will be under constant pressure to engage with markets, leading to potential mental health concerns. Maximizing productivity for traders will be key with this shift, and they will need to figure out ways to coordinate liquidity during whatever downtime they have. Artificial intelligence may also help them manage routine tasks, conduct price discovery and coordinate large-volume transactions.

Organizations will likely need to assess how best to structure employees’ schedules to maximize efficiency while also factoring in their individual strengths and preferences. Burnout prevention will be crucial, and organizations must provide support and resources toward that end. 

Implications for investor decision making

With most markets not currently operating at 24-hour capacity, investors do not necessarily act or trade immediately based on breaking news or press releases. Extended hours will bring more opportunities to act immediately upon receiving news, which could create volatility and potential gamification in the markets. For instance, the daily transaction volume surged well above average on election night in November, demonstrating the demand to make investment decisions based on news events.

This demand could lead to more potential for security pricing to be based on speculation versus business fundamentals, further fueling volatility. Capital markets organizations may be able to deploy AI to analyze trends and recognize patterns, potentially helping eliminate the emotional biases and reactionary nature of decision making when markets do shift toward this model.

Retail investors will likely also face changes. While extended trading hours might be seen as leveling the playing field between retail and institutional investors, retail investors are actually worse off when given more time to interact with the markets. Fewer participants engaging outside of peak hours can result in lower liquidity, higher volatility and wider bid-ask spreads, which can lead investors to pay more for certain securities during overnight hours. Some experts suggest that extended trading hours should be restricted to organizations that need them for business purposes. However, retail investors may want to consider adopting the methods of institutional investors by leveraging algorithmic trading and AI to support their decision making, and in turn, prevent overtrading.

Given that the current regular trading hours were put in place prior to the rise of electronic trading, when human intervention was necessary, and that most trades are now completed electronically, it’s indeed time for a change. In fact, 70% to 80% of trade volume is based on arithmetic, meaning the human factor should no longer be the primary driver for trading hours.

For investors planning to engage in 24-hour markets, here are some steps to take now to drive success:

• Ensure an adequate workforce is in place to accommodate longer business hours.
• Assess risk management policies and procedures and calibrate them to account for increased volatility, as well as potentially decreased liquidity in traditional off-market hours.
• Deploy AI tools and machine learning as appropriate to support traders and potentially automate time-intensive tasks.
• Conduct stress-testing to ensure systems can handle increased capacity in extended hours.
• Upgrade systems as needed based on those stress tests and other readiness assessments to accommodate longer hours and potentially increased system traffic.

Despite the risks that come with round-the-clock trading, this shift is inevitable and represents the future of the markets—and organizations should prepare accordingly.