Trading during the pre-market takes place before the stock market opens at 9 a.m. Eastern Time (ET) on trading days, according to Nasdaq. Traders can see market activity on the stock market at 4:15 p.m. and use this as an advantage to research leading indicators for possible investment.
Delayed trading for investors takes place after the stock market closes. Data is shown on a transmission after 15-minute intervals. Extended hours are 4 p.m. to 9 p.m. ET, and they are available for traders after the regular stock market trading day closes to allow investors to make decisions about buying stock during regular market trading hours. Investors use this information on pre-market trading to estimate the opening price of a stock.
Standard trading hours in the United States for the New York Stock Exchange and the Nasdaq Stock Market are 9:30 a.m. to 4 p.m. ET, as listed by the Nasdaq and NYSE.
Private trading using electronic communication networks (ECNs), has made it possible for investors to trade after hours. Trading outside of normal stock market hours was exclusive to higher-end stocks and institutional markets before ECNs became available.
Members of the NYSE and Nasdaq who enter stock quotes during the pre-market or extended hours sessions must comply with limited-order protection, according the Financial Regulatory Authority. These are rules from the Securities and Exchange Commission.