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S&P 500 (SPX) Up or Down on October 28?

55% say Up

Down 5 points today.

Decided by wsj.com, by October 28, 2026.

Each share pays $1 if it happens, so 55¢ means about a 55% chance.

Research, not advice. Prices from Polymarket’s international site, not available in the US.

Possible results

UpThe result is “Up”.55%
What has to happen
The official S&P 500 Index closing price for S&P 500 (SPX) on Wednesday, October 28, 2026 is higher than the official S&P 500 Index closing price for SPX on the most recent prior trading day.
DownThe result is “Down”.45%
What has to happen
The official S&P 500 Index closing price for S&P 500 (SPX) on Wednesday, October 28, 2026 is lower than the official S&P 500 Index closing price for SPX on the most recent prior trading day.

The one trap

If the two specified closing prices are exactly equal, this market will resolve 50-50.

See all fine print

If SPX does not trade at all during the regular session, the market will resolve 50-50.

Price chart

Up 55%Down 45%

-Yes chance

Recorded moves

The price fell 17.0 points in about 15 minutes, from 69¢ to 52¢. This market has no official data feed that we track.
Named source: wsj.com5m ago
The price rose 3.5 points in about 15 minutes, from 65.5¢ to 69¢. This market has no official data feed that we track.
Named source: wsj.com1h ago
The price fell 3.0 points in about 15 minutes, from 67.5¢ to 64.5¢. This market has no official data feed that we track.
Named source: wsj.com2h ago

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Show details for experienced traders

The details

Rule note: only the close countsSettled by wsj.com

Fine-print risk

Low (10/100)

settles on the condition as written

Pro adds the exact price, today’s change in points, buyers vs sellers in dollars, the price chart and every recorded move. See Pro

Official source: settlement runs on Named URL in rules: wsj.com. No recorded moves for this market yet.
Fine print: Intraday touches do not count. Only the exact closing snapshot at the cutoff timestamp settles this contract. Deadline: Wed, Oct 28, 2026, 4:00 PM ET.

Source named: wsj.com (not a tracked official feed, no release history)

Standardized read of public order book, official-source and contract-rule data, identical for every viewer. It describes the data and is not a recommendation. The venue’s published rules control settlement.

Full rules text on file (Polymarket)

This market will resolve to "Up" if the official S&P 500 Index closing price for S&P 500 (SPX) on Wednesday, October 28, 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 Wednesday, October 28, 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

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