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S&P 500 (SPX) Up or Down on September 21?
polymarket

S&P 500 (SPX) Up or Down on September 21?

Volume:
$60,240

S&P 500 (SPX) Up or Down on September 21?

 - Polymarket

S&P 500 (SPX) Up or Down on September 21? - Polymarket

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Resolved Sep 21, 2026

Closed: Sep 21, 6:34 PM EST

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S&P 500 (SPX) Up or Down on September 21?

View
100%
39%
Yes 100¢No 0.1¢
0.1¢
N/A
$60,240
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 closing price for S&P 500 (SPX) on Monday, September 21, 2026 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 closing price for S&P 500 (SPX) on Monday, September 21, 2026 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 specified closing 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 closing price published by S&P 500 Index for that shortened session will still be used for resolution. If either of the relevant days have 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 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 closing price for S&P 500 (SPX) on Monday, September 21, 2026 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 closing price for S&P 500 (SPX) on Monday, September 21, 2026 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 specified closing 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 closing price published by S&P 500 Index for that shortened session will still be used for resolution. If either of the relevant days have 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 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 direction market displays the current odds of the S&P 500 closing up or down on September 21. It also provides a price history chart showing how the probabilities have shifted over time, along with the 24-hour trading volume. Currently, the total volume for this market is $60,240, and the 24-hour volume is $55,218. This allows participants to monitor market sentiment and trading activity related to the future direction of the S&P 500.

Currently, prediction market odds offer a distinct perspective compared to traditional analyst forecasts for the S&P 500. While analysts often provide point estimates or ranges, this market aggregates the wisdom of the crowd, representing a probability distribution of potential outcomes. Discrepancies can arise due to differing methodologies, biases, or access to information. It's important to note that analyst forecasts are often based on models and assumptions, whereas this market reflects real-time betting behavior, potentially incorporating a wider range of factors and anticipating unexpected events.

This market resolves around Sep 21, 2026, with the outcome confirmed once the event is verifiable from credible public reporting. Specifically, the closing price of the S&P 500 index on September 21 will determine whether the 'Up' or 'Down' outcome is triggered. The resolution will be based on publicly available data from established financial sources. Traders will then be able to claim their winnings or adjust their strategies based on the final result of this market.

Several signals and events could significantly impact this market before Sep 21, 2026. Major economic data releases, such as inflation reports, employment figures, or GDP growth numbers, could shift investor sentiment. Unexpected geopolitical events, corporate earnings announcements from key S&P 500 companies, and changes in Federal Reserve policy are also likely catalysts. Furthermore, any surprising news regarding interest rates, global trade, or major economic disruptions could lead to substantial price movements in this market, reflecting the evolving expectations of traders.