Trading Session

A trading session is a period of time that comprises a single day of business in a financial market, from that market’s opening bell to its closing bell. Within that trading session, buyers and sellers both participate in setting current market prices, and all orders for that day must be placed within the pre-established time frame parameters of the trading session.

Trading session hours can vary by asset class and country. The regular trading session for U.S. equities starts at 9:30 a.m. and ends at 4:00 p.m. Eastern Time (ET) on weekdays, not including holidays. In 2018, for example, the stock market is closed on nine weekday holidays and it closes early at 1:00 p.m. ET on three other occasions. The regular weekday trading session for the U.S. bond market is 8:00 a.m. to 5:00 p.m. ET. In 2018, the trading session is closed on 10 weekday holidays and closes early at 2:00 p.m. on six other occasions.

The futures market has different trading hours depending upon the exchange and the type of commodity traded being traded. Traders should be aware of trading session hours for any securities and derivatives that they’re interested in trading beforehand to prevent any unexpected problems from arising.

In addition to regular trading hours, some markets may have pre-market or after-hours trading sessions. Other markets even have 24-hour trading sessions.

Pre-market trading for U.S. stocks occurs between 4:00 a.m. and 9:30 a.m. ET on weekdays. After-hours trading is from 4:00 p.m. to 8:00 p.m. ET on weekdays, although these times may vary slightly by exchange.

Pre-market and after-hours trading is a compelling way to capitalize on important news announcements or other factors that come occur of regular trading hours. With that being said, here are a number of cautions investor should be mindful of when trading outside of regular hours.

The Securities and Exchange Commission notes eight risk factors:

1. Inability to See or Act on Quotes – Some brokers only allow investors to view quotes from its own trading system rather than other ECNs.
2. Lack of Liquidity – There are fewer traders involved with after-hours trading, so there’s typically a lot less liquidity than during regular trading sessions.
3. Larger Quote Spreads – Less trading activity often translates to wider bid and ask spreads that could make order execution difficult.
4. Price Volatility – There may be greater fluctuations than during regular hours, particularly if there’s a breaking news story with significant market repercussions.
5. Uncertain Prices – The price of stocks traded after-hours may differ from those traded during regular trading sessions.
6. Bias Toward Limit Orders – Many ECNs only accept limit orders rather than market orders during after-hours sessions.
7. Competition with Professional Traders – Many after-hours traders are professionals with large institutions that have access to more information.
8. Computer Delays – There is less technical support available during pre-market or after-hours trading sessions, so you could encounter trade execution delays.

There are some markets with 24-hour trading session. Among the most notable is the global foreign exchange (forex) market, in which currencies are traded. The forex market is the largest, most liquid market in the world.

Unlike the equity market, the forex market has no physical exchange. Rather, it consists of a number of large banks and brokerage firms that trade currencies with themselves. The forex market is open 24 hours a day, five days per week, from Sunday evening until Friday night.