This market tracks whether the S&P 500 (SPX) will open higher or lower than its previous close on August 3, as measured by the official open and close prices. On Polymarket, the current probability for the leading outcome is 100%. The resolution will be based on data from https://www.wsj.com/market-data/stocks. Watch for the market to resolve following the market open on August 3.

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This market will resolve to "Up" if the official S&P 500 Index open price for S&P 500 (SPX) on August 3 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day. This market will resolve to "Down" if the official S&P 500 Index open price for S&P 500 (SPX) on August 3 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day. E.g., ordinarily, a market on Monday would refer to the previous Friday for its most recent closing price, unless that Friday were a market holiday, in which case it would refer to Thursday, or the next most recent trading day. If the two prices are exactly equal, this market will resolve 50-50. Note that all figures will be rounded to the nearest cent using standard rounding. If SPX does not trade at all during the regular session, the market will resolve 50-50. If either of the relevant days are shortened (for example, due to a market holiday schedule), the official open/close price published by S&P 500 Index for that shortened session will still be used for resolution. If the previous trading day has no official closing price (for example, due to a trading halt into the market close, system issue, delisting, or other disruption), the market will use the last valid on-exchange trade price of the regular session as the effective closing price. The resolution source for this market is the Wall Street Journal, specifically the Open/Close values published by the WSJ under "Historical Prices". US: https://www.wsj.com/market-data/stocks EMEA: https://www.wsj.com/market-data/stocks/emea ASIA: https://www.wsj.com/market-data/stocks/asia

Frequently asked questions

On Polymarket, the dashboard for the S&P 500 open direction market tracks real-time odds, price history, and 24-hour volume of $593,461. It shows how traders on Polymarket are positioning around where the index will open on August 3. The interface updates continuously, letting users monitor shifts in sentiment and liquidity as the event approaches.

This market resolves around Aug 3, 2026, with the outcome confirmed once the event is verifiable from credible public reporting. Traders will see the result posted automatically after official market data confirms the opening direction. No manual intervention is required — the system checks reputable sources against the contract terms.

Key signals include major U.S. economic reports, Federal Reserve communications, and unexpected corporate earnings shocks in S&P 500 constituents. Geopolitical developments or sudden liquidity crises could also shift trader expectations. Any development that influences early-morning futures trading or pre-market sentiment is likely to affect this market’s odds before Aug 3, 2026.

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