A stock index is a calculation of the price movements of a group of shares, so will typically only be open when the relevant exchanges are open. All three major stock indices in the US – the Dow Jones, S&P 500 and the NASDAQ 100 – follow the same times as the NYSE and the NASDAQ.
The S&P 500 and Dow Jones track the prices of stocks listed on both the NYSE and the NASDAQ, while the NASDAQ 100 is comprised solely of stocks listed on the NASDAQ.
The majority of index trading, though, is based on the prices of futures contracts – prices agreed today for a trade at a set date in the future. These contracts are bought and sold on futures exchanges, which typically have longer hours than stock exchanges.
When you see an index price quoted outside of its exchange’s opening times, you’re often seeing its futures price. With us, you can trade US stock indices 24-hours a day from 11pm Sunday until 10pm Friday (UK time). Outside regular hours, our prices are based on futures and the movements of other related markets.
When buying and selling indices with us, you can decide whether to trade at the live price (called the spot) or the futures price. You can also buy and sell indices on the weekend if you want to hedge a weekday position.
Learn more about index trading
After-hours stock trading on US shares
As well as their regular hours from 9.30am to 4pm, both the NYSE and the NASDAQ allow after-hours trading up until 8pm (New York time). They also offer a pre-market session from 4am to 9.30am (New York time). During these periods, orders are executed using technology that matches buyers and sellers automatically, called electronic communication networks (ECNs).
The NYSE and the NASDAQ are the world’s biggest and second-biggest exchanges respectively. Offering these extended hours enables them to cater to the high volume of trades they see each day.
However, pre-market and after-hours periods tend to see a drop off in volume from standard hours. This dampens liquidity and can lead to heightened volatility, which may increase risk.
