Polymarket vs. Kalshi
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See where the two biggest prediction markets disagree. Pick any two markets, or start from the biggest gaps below: prices, volume, history and the resolution rules, side by side.
Will Donald Trump and Marco Rubio be the 2028 Republican Presidential ticket?
Vol $0 today · $568 total
Will Donald Trump win the 2028 Republican presidential nomination?
Vol $468 today · $9.7M total
Both markets price this about the same, around 2%.
History starts when we first saw each market, so a newly added market has a short line.
| Kalshi | Polymarket | |
|---|---|---|
| Probability (Yes) | 1% | 2% |
| Change (24h) | +0.0 pt | +0.0 pt |
| Volume today | $0 | $468 |
| Total volume | $568 | $9.7M |
| Liquidity | — | $355.1K |
| Open interest | $568 | — |
| Resolves | 25mo | 25mo |
| Tracked for | 11 days | 11 days |
Resolution rules: read both before trusting a gap
Kalshi
If the Republican presidential nominee is Donald Trump AND the Republican vice presidential nominee is Marco Rubio in the 2028 presidential election, then the market resolves to Yes.
Polymarket
This market will resolve to “Yes” if the named individual wins and accepts the 2028 nomination of the Republican Party for U.S. president. Otherwise, this market will resolve to “No”. The resolution source for this market will be a consensus of official Republican Party sources. Any replacement of the Republican nominee before election day will not change the resolution of the market.
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Informational only — not financial advice. Odds are mirrored from each platform and may lag the live order book.