The stock market is going 24 hours, 7 days a week

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The stock market’s genteel 9:30-to-4 workday, complete with opening and closing bells that date back to the 1870s, is becoming as anachronistic as the headsets still worn on the New York Stock Exchange floor. Now Wall Street is racing to embrace the always-on ethos of cryptocurrency and prediction markets, and meet the demands of a new generation of retail traders hooked on round-the-clock action.

Major U.S. exchanges, including the NYSE and Nasdaq, are pushing to extend trading to 22 and 24 hours, respectively, with some platforms hoping to launch before year’s end. The shift — driven by surging retail investor participation that now accounts for at least 20% of daily U.S. trading volume and a global appetite for the trillions of American equities — represents the most fundamental change to market structure since electronic trading replaced the trading floor.

But the move toward 24/7 markets, already embraced by brokerages like Robinhood and Charles Schwab through “dark pools” and alternative trading systems, raises critical questions about price volatility, market manipulation, and whether turning stock trading into an endless casino will benefit everyday investors — or simply give them more opportunities to lose money.

The push for perpetual trading reflects a fundamental shift in how Americans interact with financial markets. Everything is becoming a betting opportunity. Polymarket turned the presidential election into a billion-dollar wagering pool where traders could bet on electoral outcomes in real-time. People are now perpetually online, scanning X, deep in their favorite subreddits, treating every news cycle, every earnings report, every geopolitical tremor as a chance to strike it rich.

This is exactly the behavior Wall Street is now addicted to. Blue Ocean Technologies, which powers overnight trading for several brokerages, facilitated $3.3 billion in trades during the overnight session following Election Day last November, more than triple its typical $1 billion overnight volume, according to The Wall Street Journal. Robinhood’s sixth-busiest overnight session ever came after Nvidia’s recent earnings report. These aren’t professional traders executing complex strategies. They’re people in their pajamas making supersize bets based on breaking news, memes, and gut feelings.

The traditional trading day already seems quaint when you consider that cryptocurrency trades 24/7, foreign exchange never sleeps, and American Treasury bonds trade around the clock. Polymarket and other prediction platforms have shown there’s an insatiable appetite for turning every event into a financial position. Why shouldn’t you be able to bet on Tesla’s stock price at 3 a.m. the same way you can bet on whether Trump will post on social media before noon?

But there’s something dystopian about this vision of perpetual market access. The after-hours trading that exists today already demonstrates the dangers. Liquidity evaporates when most traders are asleep, meaning buyers and sellers are harder to match. Spreads widen, making trades more expensive. Prices swing wildly on thin volume. The National Best Bid and Offer protections that ensure investors get fair prices during regular hours don’t operate around the clock.

These aren’t bugs in the system. They’re features for sophisticated players who know how to navigate them. Institutional investors have used “dark pools” for decades to execute large trades without moving markets. The pools got their ominous name because trades only become public after execution, allowing big players to operate in the shadows. Now retail investors are being invited into these same murky waters, armed with smartphones and Reddit threads instead of Bloomberg terminals and risk management systems. Usually the house money is, well, their house.

Some economists worry that 24/7 trading could actually lead to worse price discovery and lower returns, not better ones. The self-fulfilling nature of current trading patterns, where volume concentrates around the opening and closing auctions precisely because that’s when everyone else is trading, suggests that spreading activity across 24 hours might just create 24 hours of inefficient pricing.

But the markets are moving. The SEC has already approved 24X National Exchange, which is a brand new exchange built specifically for 23-hour trading days. Meanwhile, brokerages keep expanding: Webull recently opened overnight trading to U.S. users, while Firstrade plans to launch next year. Foreign ownership of U.S. equities has almost doubled since 2019, and investors from Tokyo to London want access during their waking hours.

The Polymarket phenomenon shows where this is heading. When a platform for betting on election outcomes can move from obscurity to processing billions in wagers seemingly overnight, it reveals an uncomfortable truth about modern markets.

We’re not investing anymore. We’re not even really trading. We’re just gambling, and Wall Street wants to make sure the casino never has to close.