After-hours trading, also known as extended-hours trading, refers to trading that occurs outside of regular trading hours. Regular trading hours for stocks traded on exchanges and certain other markets are from 9:30 a.m. to 4:00 p.m. Eastern Time. After-hours trading sessions may occur before or after regular trading hours. The duration of after-hours trading sessions varies between markets and trading venues. Investors should contact their brokerage firms to determine if and when after-hours trading sessions are available.