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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.