🇺🇸BREAKING: U.S. stock markets will begin trading 23 hours a day, 5 days a week from December 6 The planned trading week will run from Sunday evening through Friday evening, with a one-hour daily maintenance break. Nasdaq and NYSE Arca are among the venues preparing for expanded hours, while the regular 9:30 a.m. – 4 p.m. session remains unchanged. The SEC is upgrading market infrastructure for 23/5 trading, with full 24/7 trading potentially coming later. Brokers will decide which securities and overnight services customers can access, while thinner liquidity could mean wider spreads and greater volatility.