TOTAL VOLUME:
$54.3b
24H VOL:
$198,896,558
OPEN INTEREST:
$1,191,591,877
500,572
Markets across
13,691
events
MATCHED EVENTS:
1,797
PLATFORM COVERAGE:
4
Polymarket:
51%
VS.
Kalshi:
49%
S&P 500 (SPX) Up or Down on March 25?
Volume:
$415,221
Outcome
Chance %
Price
Liquidity
Volume
24h
7d
Open Interest
Ends in
Result
Trade
Description
This event group tracks whether the S&P 500 Index closes higher or lower on Wednesday, March 25, 2026, compared to the most recent prior trading day. Both platforms measure the same underlying outcome—directional movement of SPX on a specific date—using the official closing price as the settlement value.
PredictionHero - Resolution Divergence Alerts (RDA)
Divergence Detected
Issue:
Polymarket and Kalshi use fundamentally incompatible resolution frameworks. Polymarket resolves based on directional price movement (Up/Down vs. prior trading day), while Kalshi contains 60 separate binary conditions all resolving to Yes based on absolute index thresholds, with no corresponding No resolution criteria, making Kalshi's market logically incoherent and unresolvable.Hero Tip:
Do not trade these markets as a unified group. Polymarket's Up/Down binary is a standard directional bet. Kalshi's structure is broken: all 60 conditions resolve to Yes if SPX closes above various thresholds (ranging from 5824.9999 to 7299.9999), but there is no explicit No resolution path. If SPX closes below 5824.9999, all 60 conditions fail, but Kalshi does not specify what happens then—the market cannot resolve. Avoid Kalshi entirely until the platform clarifies the No resolution logic.Critical Divergence Points:
- Polymarket: Distinct stance: Resolves based on directional price movement. Market resolves Up if March 25 closing price is higher than the most recent prior trading day's close, Down if lower, and 50-50 if equal or no trade occurs. Source is Wall Street Journal Historical Prices. This is a binary directional comparison, not an absolute threshold test.
- Kalshi: Outlier: Provides 60 separate binary conditions, each stating 'If end-of-day SPX on March 25 is above [threshold X], then resolves to Yes.' Thresholds range from 5824.9999 to 7299.9999. No explicit No resolution criteria are provided. If SPX closes below the lowest threshold (5824.9999), all 60 conditions fail and the market's resolution outcome is undefined, creating a logical gap that prevents settlement.
Our PredictionHero Resolution Divergence Alerts (RDA) are there to help users identify potential differences across platforms. They do not replace or supersede the official rules and description of any prediction market. Users are solely responsible for reviewing and understanding the applicable rules and resolution criteria before placing any trade or bet. If you notice a potential inconsistency, discrepancy, or error in an alert, please report it to our team so we can review and improve the accuracy of our data.
Follow the signals, not the noise
Get insights on market conviction, notable shifts, and what the data is quietly signaling.
PredictionHero © 2026 · v0.13.0PredictionHero provides aggregated market data and informational signals only. Nothing on this site constitutes financial, legal, or investment advice. Markets are volatile and speculative. Past performance does not guarantee future results. Always do your own research and consult qualified professionals before making decisions involving risk.