Kalshi hits a record $19B week as Polymarket US triples fall trade volume

Kalshi sets a weekly record

Kalshi recorded its largest trading week at $19B, according to DeFi Rate’s Oct 12 report, marking a new volume high for the prediction-market exchange.

DeFi Rate’s tally also put trading across 9 prediction-market exchanges at $3.6B over the last 24 hours. That aggregate counts contracts at $1, a measurement convention that matters when comparing it with other volume figures.

The report’s headline also indicated that Polymarket US tripled its fall trading volume. The available material does not specify the comparison period or provide an absolute volume figure for Polymarket US.

The figures describe different windows and scopes: Kalshi’s record covers a week, while the $3.6B total spans 24 hours across multiple exchanges. With the full source text unavailable, the supplied summary does not establish individual exchanges’ shares of that daily total.

What it means for prediction markets

• Volume comparisons need consistent definitions. The $3.6B daily aggregate uses contracts counted at $1; it should not automatically be equated with figures calculated on another basis.
• The growth signals have limits. Kalshi’s weekly record and Polymarket US’s reported tripling indicate increased activity, but the available material does not identify which contracts drove it or establish whether it will persist.