Kalshi sets back-to-back daily volume records as parlays drive 70% of trading

Kalshi just had the busiest weekend in its history. Then it topped that the next day.

The CFTC-regulated prediction market recorded $3.91 billion in notional volume on October 10, 2026, followed by $3.96 billion on October 11. Both figures beat the prior single-day high of $3.68 billion, set on October 4. That record had been standing for a grand total of one week.

The catch, if you want to call it that: roughly 70% of the action came from parlay-style “combo” contracts. Those products inflate headline numbers in ways that deserve a closer look.

Inside the record weekend

Combo contracts accounted for approximately 70% of total volume on both days. That works out to about $2.80 billion on Saturday and about $2.75 billion on Sunday.

Much of Kalshi’s parlay volume came from long-shot combinations priced below 1 cent. Notional volume counts the full potential payout value of a contract, not the cash a trader actually puts at risk. A trader buying a sub-penny parlay might commit very little money while generating a large notional figure. The real risk absorbed by traders on these combo trades is considerably lower than the $3.96 billion headline suggests.

Zoom out to the full week and the numbers stay large. From October 5 to 11, Kalshi logged $19.03 billion in total weekly notional volume. Its trailing 30-day volume exceeded $73 billion.

Football season and the combo boom

Both the NFL and NCAA football seasons are in full swing, and sports have become a central driver of prediction market activity. Combined weekend trading activity across Kalshi and rival Polymarket surpassed $8.5 billion, with football giving both venues a major lift.

Since mid-September, Kalshi’s volume has cleared $3 billion on several days, and its year-to-date cumulative activity has reached into the hundreds of billions. Kalshi has steadily expanded its sports offerings, and the combo products it introduced in 2025 caught on fast with users.

The regulatory shadow over the volume surge

Certain Kalshi contracts look a great deal like sports wagering, which in the US is regulated at the state level. Kalshi operates under federal CFTC oversight as a prediction market, and its sports contracts have drawn ongoing legal scrutiny from those who argue the products are sports betting under a different name.

The combo boom sharpens that debate. A multi-leg parlay priced below a penny is harder to distinguish from what a traditional sportsbook sells.

What this means for the prediction market race

Weekly volume above $19 billion and a 30-day figure north of $73 billion point to serious appetite for speculative, event-driven trading. When roughly 70% of volume comes from low-priced parlays, notional volume becomes a less reliable gauge of how much money is genuinely moving. A volume record built on sub-penny long shots is still a record, but it is not the same as billions in conviction trades.

The more Kalshi’s growth depends on sports parlays, the more its business is exposed to the outcome of scrutiny over whether those contracts are prediction markets or sports wagers. Any ruling that narrows what Kalshi can offer could hit the exact product line that powered this weekend’s records.