Guide · Basics
Stock Index Futures Explained: What 'Nasdaq Futures Are Up 1%' Means Before the Open
At 05:00 UTC on October 19, 2026, Nasdaq 100 futures were up 1.3% from Friday's settlement while the stock market itself had been closed for sixty hours. A guide to what index futures are, who trades them overnight, how the percentage on the screen is calculated, and why the number tells you about the open but not about the close.
A stock index future is a contract to exchange the cash value of an index at a fixed date in the future. The three everyone quotes are the E-mini S&P 500, the E-mini Nasdaq 100 and the E-mini Dow, all traded on the CME, and they are the reason a headline can say "stocks are up" at 5 a.m. when no stock has traded since 4 p.m. the previous day. The contracts trade from 6 p.m. Eastern on Sunday to 5 p.m. on Friday with a one-hour pause each afternoon, so for 23 hours a day there is a live price for the US market, set by traders in Asia and Europe, by US desks working overnight and, increasingly, by retail accounts.
The percentage on the screen is measured against the previous session's settlement, which is set near the 4 p.m. cash close, not against where the futures were trading at some earlier point in the night. So "Nasdaq futures up 1%" at 5 a.m. means the contract is 1% above Friday's settlement; it does not mean anything rose at 5 a.m., and it may already have been up 1.5% at 2 a.m. Each contract has a multiplier: the E-mini S&P 500 is $50 times the index, so at 7,766 one contract controls about $388,000 of exposure, and the E-mini Nasdaq 100 is $20 times the index, or about $596,000 at 29,785. Micro contracts at one tenth of those sizes exist for smaller accounts. Positions are held on margin that is a small fraction of the notional, which is why these are instruments for hedging and short-term positioning rather than for owning the market.
Futures trade at a slight premium or discount to the index itself, called fair value, equal to the cost of financing the position until expiry minus the dividends the stocks would pay in the meantime. When commentators say "futures are up 30 points but fair value is 20", they mean the market is really implying a 10-point higher open. Contracts expire on the third Friday of March, June, September and December, and the quoted price switches from one contract to the next about a week before, which produces a one-off jump in the level that is not a market move. The December 2026 contract was the one quoted in October.
Monday, October 19, 2026 is a clean example of what the overnight price does and does not tell you. The Nasdaq composite had fallen 2.15% on Friday, its worst week since June, and Nasdaq 100 futures had settled at 29,391.50. When Asia opened, Korea's Kospi fell 3.2% at the open and Japan's Nikkei 2.3%, but the futures did not follow them down; they rose from the Sunday evening open, and by 05:00 UTC, with the Kospi back above Friday's close and China's GDP report having beaten forecasts, the December contract was at 29,785, up 1.3%. S&P 500 futures were up 0.8% and Dow futures 0.5%. A trader in Europe arriving at 7 a.m. knew that the US market was likely to open higher, that the Friday afternoon sell-off had found buyers, and that the hedge fund rumour that lifted the VIX on Friday had not been confirmed over the weekend. That is useful information.
What the futures did not tell that trader is where the Nasdaq would close. Overnight liquidity is thin, especially between 2 a.m. and 5 a.m. Eastern, and a move of 1% in the futures can represent a fraction of the volume that trades in the first ten minutes after 9:30 a.m. Overnight gains are frequently faded at the open, and large overnight losses are frequently bought; the day session is a different market with different participants, and the futures price at 5 a.m. is a forecast of the open, not of the day. Earnings reports after the close show the same thing in reverse: a company's shares may move 8% at 4:05 p.m. while index futures barely twitch, and the index reaction appears only when the whole market reprices at the next open.
Practical uses follow. Check futures before the open to know the direction and rough size of the gap, and compare them with fair value if the number is small. Watch them around overseas data releases, as on China's GDP day, because they are the only US market that reacts in real time. Use them, or the micro contracts, to hedge a portfolio overnight when holding individual stocks through an event feels wrong. And treat any overnight move of more than 1% as provisional until the first half-hour of regular trading has confirmed it: the futures tell you what the people awake at 5 a.m. think; the open tells you what everyone thinks.