Private Company Insights: Kalshi and Polymarket

Preview

This report examines the business performance, competitive positioning and market activity of Kalshi and Polymarket within the prediction markets sector. Both companies operate platforms where participants can trade contracts tied to the outcomes of future events across areas such as politics, sports and economics. The report assesses their business models, trading activity, market offerings, regulatory frameworks, funding and corporate development using publicly available information and MSCI Private Company Insights data.

The report also places both companies in the context of the broader private growth market, using the year-to-date performance of the PM50 Growth against selected public-market indexes and the performance of the 10 most active private companies across sectors.

Highlights:

• 90-day composite price performance: Polymarket ranked fourth and Kalshi ranked eighth among the 10 most active private-market companies and delivered returns of -5.8% and +80.32%, respectively, over the 90 days to Sept. 21, 2026.
• Largest bid-side volume in 2026: As of Sept. 21, 2026, Kalshi recorded its highest bid-side volume in Q3 2026 at USD 586.1 million, representing 17% of total bid-ask volume. Polymarket recorded its highest bid-side volume in Q1 2026 at USD 182.5 million, representing 15% of total bid-ask volume.
• Largest ask-side volume: As of Sept. 21, 2026, Kalshi had surpassed its previous quarterly peak in ask-side volume, reaching USD 2.83 billion, which represented 83% of its total bid-ask volume. Over the same period, Polymarket recorded USD 1.52 billion in ask-side volume, representing 95% of its total bid-ask volume.