#SEC推进美股24小时交易 SEC moves to enable 24-hour trading of U.S. stocks: a transformation reshaping the global market landscape

On July 23, 2026, the U.S. Securities and Exchange Commission (SEC) officially released a draft for public comment, proposing to push U.S. stock exchanges to achieve “around-the-clock 24-hour trading,” covering all weekday hours and selected periods on weekends. Once implemented, the proposal would completely break the “nine-to-five” tradition that has endured for more than two centuries since the 1792 Buttonwood Agreement, and is widely seen as the most profound institutional reform after the digitization of trading.

The SEC’s motivation is clear and urgent. On the one hand, cryptocurrency and foreign exchange markets have long operated 24/7, and large numbers of U.S. retail investors have been forced into higher-risk offshore venues during non-trading hours as the regulatory vacuum has grown. On the other hand, investors in Asia and Europe have long been constrained by time zone differences; if U.S. stocks move to 24-hour trading, its global asset pricing power would be significantly strengthened. According to internal SEC estimates, extending trading hours could increase U.S. stocks’ average daily trading volume by about 15%-20% and attract more than $100 billion in additional new international capital.

However, the cost of change is equally heavy. First is the structure of market liquidity—during overnight and weekend periods, market-maker participation is bound to decline, and bid-ask spreads could widen sharply, exposing retail investors to higher slippage risk. Second, the settlement cycle, risk monitoring, and corporate information disclosure mechanisms would all need to be comprehensively rebuilt, and the earnings-reporting window for listed companies would also have to be adjusted. Even more concerning for the market is that high-frequency trading algorithms may exacerbate abnormal price volatility during periods of thinner liquidity; the lesson from Japan’s 2025 “flash crash” remains close at hand.

The SEC said it will adopt a phased approach: initially, it may only open 22-hour trading for S&P 500 index constituents and set circuit-breaker thresholds. But in any case, the era of nonstop U.S. stock markets is already in its countdown. This transformation is both an inevitable requirement for global capital flows and the ultimate test of regulatory wisdom and market resilience—when the bell at the New York Stock Exchange no longer keeps ringing, the global financial clock will be recalibrated.