# 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._ **Published:** 2026-07-18 **Source:** https://www.startuphub.ai/ai-news/prediction-markets/2026/prediction-market-arbitrage-12-live-opportunities-as-of-july-18-2026-july-18-2026 --- 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. Arbitrage ROI by event. French presidential electio...: ROI % 35.14. Who will advance in the Bra...: ROI % 13.64. Will Congress override Trum...: ROI % 6.38. Who will be the next Suprem...: ROI % 6.04. Who will win the 2028 US pr...: ROI % 5.65. French presidential electio...: ROI % 4.17. Cross-venue spreads on July 18, 2026. Source: StartupHub.ai arbitrage engine. **Live arbitrage right now** These update automatically. Tap a leg to open the venue. Not financial advice. - **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](https://www.predictit.org/markets/detail/8766/Who-will-win-the-next-French-presidential-election) at 50c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxfrpresadvance) 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](https://www.predictit.org/markets/detail/8544/Who-will-win-the-2026-Brazilian-presidential-election) at 78c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxbrpresadvance) 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](https://www.predictit.org/markets/detail/8480/Will-Congress-override-a-veto-in-2026) at 23c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxvetooverride) at 71c. - **Who will be the next Supreme Court justice? Will Emil Bove become the next Justice on the Supreme Court?**. Arbitrage: 6.0% ROI, locks 6c per $1. Buy YES on [Kalshi / Robinhood](https://kalshi.com/markets/kxscourt) at 5c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8246/Who-will-be-the-next-Supreme-Court-nominee) at 89c. - **Who will win the 2028 US presidential election?, Gavin Newsom**. Arbitrage: 5.7% ROI, locks 5c per $1. Buy YES on [Polymarket](https://polymarket.com/event/will-gavin-newsom-win-the-2028-us-presidential-election) at 12c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8171/Who-will-win-the-2028-US-presidential-election) at 83c. - **French presidential election: who will advance? Will Jordan Bardella qualify for the runoff in the 2027 French presidential election?**. Arbitrage: 4.2% ROI, locks 4c per $1. Buy YES on [Kalshi / Robinhood](https://kalshi.com/markets/kxfrpresadvance) at 7c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8766/Who-will-win-the-next-French-presidential-election) at 89c. - **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](https://kalshi.com/markets/kxvpresnomd) at 4c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8799/Who-will-win-the-2028-Democratic-vice-presidential-nomination) 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](https://polymarket.com/event/will-rahm-emanuel-win-the-2028-democratic-presidential-nomination-299) at 2c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxpresnomd) at 95c. - **2028 Democratic presidential nominee Will Kamala Harris be the Democratic Presidential nominee in 2028?**. Arbitrage: 3.3% ROI, locks 3c per $1. Buy YES on [PredictIt](https://www.predictit.org/markets/detail/8171/Who-will-win-the-2028-US-presidential-election) at 5c, buy NO on [Kalshi / Robinhood](https://kalshi.com/markets/kxpresnomd) at 92c. - **2028 Democratic presidential nominee Will Mark Kelly be the Democratic Presidential nominee in 2028?**. Arbitrage: 3.2% ROI, locks 3c per $1. Buy YES on [Polymarket](https://polymarket.com/event/will-mark-kelly-win-the-2028-democratic-presidential-nomination-479) at 1c, buy NO on [PredictIt](https://www.predictit.org/markets/detail/8153/Who-will-win-the-2028-Democratic-presidential-nomination) at 96c. [See the full live arbitrage board](https://www.startuphub.ai/arbitrage) or poll the free [JSON API](https://www.startuphub.ai/api/v1/arbitrage). ## 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](https://www.startuphub.ai/arbitrage), 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](https://www.startuphub.ai/api-docs/reference/arbitrage) or open the [live JSON endpoint](https://www.startuphub.ai/api/v1/arbitrage). *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.* --- Original analysis from [startuphub.ai](https://www.startuphub.ai), the #1 AI startup directory.