Prediction Market Arbitrage: 12 Live Opportunities as of July 18, 2026 (July 18, 2026)

Our cross-venue engine identified 12 live prediction market arbitrage opportunities today, allowing for guaranteed returns by simultaneously buying YES and NO on the same event across different platforms.

Live prediction market arbitrage board across Polymarket, Kalshi and PredictIt on July 18, 2026
Key Takeaways
  • 1
    12 live prediction market arbitrage opportunities identified across Polymarket, Kalshi/Robinhood, and PredictIt.

  • 2
    The most lucrative live opportunity offers a 35.1% ROI on the 2027 French presidential election.

  • 3
    Opportunities range from 3.1% to 35.1% ROI, with spreads closing fast.

  • 4
    Arbitrage involves buying YES on one venue and NO on another for under $1 total, locking a guaranteed profit.

StartupHub.ai's proprietary cross-venue engine has surfaced 13 prediction market arbitrage opportunities as of July 18, 2026. An arbitrage lock occurs when buying a 'YES' contract on one venue and a 'NO' contract on another for the same real-world event costs less than $1 combined, guaranteeing a payout of the difference.

Twelve of these opportunities are live right now, offering immediate potential for guaranteed returns. The remaining one was seen earlier today and may have already closed, as spreads on these markets can move very quickly. It is crucial to remember that this is not financial advice, and potential returns can be impacted by fees, KYC requirements, and withdrawal limits on each platform.

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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Daniel Singer

Written by

Daniel Singer

Editor, StartupHub.ai

Daniel Singer is the editor of StartupHub.ai, a technology expert and thought leader on AI and its applications across sectors, from fintech and healthcare to developer tooling and consumer software. He writes and tests the tools covered here thoroughly and regularly, and built StartupHub.ai to give founders, operators and buyers a clearer read on what they are actually being sold.

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