Kalshi and Polymarket reached $1.44 billion in trading volume in September, with prediction markets attracting accelerating institutional capital inflows.

According to ChainCatcher, citing The Block, the prediction market continues to heat up, with Kalshi and Polymarket achieving a combined trading volume of $1.44 billions in September, setting a new historical record. Recently, both platforms announced the completion of new funding rounds: Polymarket raised $2 billions from Intercontinental Exchange (ICE), bringing its valuation to $9 billions; Kalshi raised $300 millions at a $5 billions valuation.

This round of financing has produced at least one new billionaire, with Polymarket founder Shayne Coplan becoming the youngest self-made billionaire. Data shows that in September, Kalshi's market share once rose to 60%, reversing the pattern dominated by Polymarket at the beginning of the year.

The two platforms have significant differences in technical architecture: Kalshi operates off-chain, with data accessible only via API; Polymarket operates entirely on-chain, with all markets and positions publicly available for inquiry. Analysts believe that Kalshi's recent surge in trading volume is partly due to its partnership with Robinhood, which now allows users to directly participate in Kalshi's sports prediction market trading through its interface. This also marks the accelerated integration of prediction markets into the mainstream financial ecosystem.