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S&P 500 (SPX) Opens Up or Down on July 20?
polymarket

S&P 500 (SPX) Opens Up or Down on July 20?

Volume:
$53,622

S&P 500 (SPX) Opens Up or Down on July 20?

 - Polymarket

S&P 500 (SPX) Opens Up or Down on July 20? - Polymarket

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Resolved Jul 20, 2026

Closed: Jul 20, 4:00 PM EST

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S&P 500 (SPX) Opens Up or Down on July 20?

View
100%
Yes 100¢No 0¢
0.1¢
N/A
$53,622
N/A
N/A
N/A
Settled
Yes
Total markets: 1

Description

This market will resolve to "Up" if the official S&P 500 Index open price for S&P 500 (SPX) on July 20 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 July 20 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

Polymarket

This market will resolve to "Up" if the official S&P 500 Index open price for S&P 500 (SPX) on July 20 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 July 20 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 S&P 500 opening direction market dashboard displays real-time odds and historical price movements for whether the index will open higher or lower on July 20. Traders use this interface to monitor current probabilities, review 24-hour volume of $51,972, and track how sentiment shifts as market hours approach. The dashboard aggregates all buy and sell orders on this single venue, giving you a live snapshot of how prediction market participants are positioning themselves ahead of the opening bell.

Prediction market odds often diverge from traditional analyst sentiment because they reflect real financial incentives—traders profit or lose based on accuracy. While financial analysts may issue directional calls based on overnight news, earnings, or economic data, this market prices in the collective judgment of all active traders betting real capital. Comparing the odds here to published analyst reports on S&P 500 positioning can reveal where consensus breaks down and highlight which forecasts carry the most conviction among market participants.

On Polymarket, prices reflect that venue's order book, liquidity, and how traders price the outcome right now. On Polymarket, this market uses an automated market maker model where the price of each outcome (up or down) is determined by the ratio of shares held in the liquidity pool. As traders buy shares predicting an up opening, the up price rises and the down price falls, and vice versa. This continuous pricing mechanism ensures the market stays liquid and reflects real-time shifts in trader conviction as new information emerges.

This market resolves around Jul 20, 2026, once the S&P 500's opening level for that date is verified against credible public sources. The outcome is determined by whether the index opens above or below its previous close. Resolution is straightforward and objective, tied to widely reported market data that leaves no room for ambiguity or dispute.

Overnight economic data, Federal Reserve communications, geopolitical developments, and earnings surprises can all shift opening direction expectations. Futures markets trading during extended hours provide early signals that often flow into this prediction market as traders adjust positions. Volatility spikes, changes in Treasury yields, or unexpected corporate news can trigger sharp repricing. Monitoring financial news and futures activity in the hours before the opening bell is essential for tracking how this market evolves.