<P> Extended - hours trading is stock trading that happens either before or after the normal trading hours of a stock exchange, i.e., pre-market trading or after - hours trading . </P> <P> After - hours trading is known as the buying and selling of securities when the major markets are closed . Since 1985, the regular trading hours for major exchanges in the United States, such as the New York Stock Exchange and the Nasdaq Stock Market, have been from 9: 30 a.m. to 4: 00 p.m. Eastern Time (ET). Pre-market trading occurs from 4: 00 a.m. to 9: 30 a.m. ET, although the majority of the volume and liquidity come to the pre-market at 8: 00AM ET . After - hours trading on a day with a normal session occurs from 4: 00 p.m. to 8: 00 p.m. ET . Market makers and specialists generally do not participate in after hours trading, which can limit liquidity . </P> <P> Trading outside regular hours is not a new phenomenon but used to be limited to high - net - worth investors and institutional investors like mutual funds . The emergence of private trading systems, known as electronic communication networks (ECNs), has allowed individual investors to participate in after - hours trading . </P>

When does after hours trading start and end