Prediction Market Arbitrage: 10 Opportunities Surfaced by StartupHu…

StartupHub.ai's proprietary cross-venue engine has identified 10 prediction market arbitrage opportunities as of July 21, 2026. An arbitrage lock occurs when the combined price of buying a 'YES' contract on one platform and a 'NO' contract for the same real-world event on another platform totals less than $1, guaranteeing a profit regardless of the outcome.

These opportunities span major prediction market venues including Polymarket, Kalshi/Robinhood, and PredictIt. While 9 of these spreads are currently live, it's crucial to remember that prediction market prices are highly dynamic and can close rapidly. Potential investors should also factor in platform fees, KYC requirements, and withdrawal limits, which can impact overall returns.

Live arbitrage right now These update automatically. Tap a leg to open the venue. Not financial advice.

Who will be the Prime Minister of Israel after the 2026 election?, Benjamin Netanyahu. Arbitrage: 51.5% ROI, locks 34c per $1. Buy YES on Kalshi / Robinhood at 8c, buy NO on PredictIt at 58c.
French presidential election: who will advance? Will Marine Le Pen qualify for the runoff in the 2027 French presidential election?. Arbitrage: 35.1% ROI, locks 26c per $1. Buy YES on PredictIt at 50c, buy NO on Kalshi / Robinhood at 24c.
Who will advance in the Brazilian presidential election? Luiz Inácio Lula da Silva. Arbitrage: 13.6% ROI, locks 12c per $1. Buy YES on PredictIt at 78c, buy NO on Kalshi / Robinhood at 10c.
Will Congress override Trump's veto? Will Congress ever override Trump's veto?. Arbitrage: 6.4% ROI, locks 6c per $1. Buy YES on PredictIt at 23c, buy NO on Kalshi / Robinhood at 71c.
Who will be the next Supreme Court justice? Will Emil Bove become the next Justice on the Supreme Court?. Arbitrage: 6.2% ROI, locks 6c per $1. Buy YES on Kalshi / Robinhood at 5c, buy NO on PredictIt at 89c.
Who will win the 2028 US presidential election?, Gavin Newsom. Arbitrage: 5.5% ROI, locks 5c per $1. Buy YES on Polymarket at 12c, buy NO on PredictIt at 83c.
2028 Democratic VP nominee Will Josh Shapiro be the nominee for the Vice Presidency for the Democratic party?. Arbitrage: 4.1% ROI, locks 4c per $1. Buy YES on Kalshi / Robinhood at 4c, buy NO on PredictIt at 92c.
2028 Democratic presidential nominee Will Rahm Emanuel be the Democratic Presidential nominee in 2028?. Arbitrage: 3.5% ROI, locks 3c per $1. Buy YES on Polymarket at 2c, buy NO on Kalshi / Robinhood at 95c.
French presidential election: who will advance? Will Jordan Bardella qualify for the runoff in the 2027 French presidential election?. Arbitrage: 3.1% ROI, locks 3c per $1. Buy YES on Kalshi / Robinhood at 8c, buy NO on PredictIt at 89c.
2028 Democratic presidential nominee Will Mark Kelly be the Democratic Presidential nominee in 2028?. Combined cost 98c (no lock right now). Buy YES on Polymarket at 2c, buy NO on PredictIt at 96c.

See the full live arbitrage board or poll the free JSON API.

Track these live, or poll the free API

The board above refreshes on its own, so this page stays current long after today. The full cross-venue feed lives on the arbitrage board, and every match is also a free JSON API and an MCP tool, so a trading agent can poll live Polymarket, Kalshi and PredictIt arbitrage opportunities and act on them.

curl https://www.startuphub.ai/api/v1/arbitrage?arbs_only=1

Read the arbitrage API reference or open the live JSON endpoint.

Informational feed, not financial advice. Live arbitrages are often fleeting, and fees, gas, KYC and withdrawal limits eat into the spread. Verify each market’s resolution rules and costs before trading.

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Prediction Market Arbitrage: 10 Opportunities Surfaced by StartupHub.ai Engine (July 21, 2026)

Track these live, or poll the free API