Kalshi Tops $5 Billion in Daily Trading Two Days Running, Mostly on Parlays

Kalshi traded more than $5 billion in notional volume on both Saturday and Sunday, a first for the prediction market on consecutive days. Its daily data files show $5.33 billion and $5.36 billion, both above its previous record of $5.30 billion.

Combos, the exchange 's multi-leg contracts that work like a parlay, made up 75.6% of Saturday's volume and 74.6% of Sunday's. In July they were 36% of contracts traded on Kalshi and carried an average implied probability of 9%, against 43% for other contracts, a Bloomberg analysis showed.

The weekend followed a filing on Friday in which the American Gaming Association (AGA), the casino industry's trade group, told a federal appeals court that those combos are ordinary sports parlays.

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A Daily Record Four Times Higher Than in June

The October 24 peak lasted two weeks. Kalshi's record day has grown more than fourfold since the summer. The exchange first passed $1 billion in a single day in June, when World Cup markets lifted a Sunday to $1.236 billion, according to DeFi Rate.

DeFi Rate reported a first $3 billion day on September 20, and Bitcoin.com News counted $3.96 billion on October 11. Sunday's $5.36 billion is about 4.3 times the June mark, by FinanceMagnates.com's calculation.

The wider market grew with it. Combined monthly taker volume at Kalshi, Polymarket and Polymarket's US venue reached $172.4 billion in the third quarter, against $98.5 billion in the second, FM Intelligence calculations show.

What the Notional Figure Counts

Notional volume values every contract at its full $1 payout, not at the price a trader paid. A long-shot combo bought for a few cents therefore adds a dollar per contract to the total.

Most of the weekend's combos were long shots. For 85% of Saturday's combo volume and 79% of Sunday's, no contract in the market traded above 5 cents that day, by FinanceMagnates.com's count from Kalshi's files.

One cross-category combo series carried most of the weekend, with $3.92 billion on Saturday and $3.23 billion on Sunday. A second combo series rose to $763 million on Sunday from $110 million a day earlier.

IG Group Chief Executive Breon Corcoran, whose company is buying US operator Underdog, questioned in October what such volume records are worth, saying a $1 parlay can carry a notional value in the thousands.

Outside combos, 15-minute bitcoin contracts were the largest series on both days, at $259 million and $282 million. College football game markets drew $258 million on Saturday and NFL game markets $241 million on Sunday.

Gaming Industry Tells Court Combos Are Parlays

The AGA filed its amicus brief in Kalshi's appeal against New York at the US Court of Appeals for the Second Circuit. It said Kalshi offers "garden-variety sports bets, such as point spreads, proposition bets, and parlays."

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Citing data from Event Horizon, the brief said parlays make up two-thirds of Kalshi's volume and that 55% of them are long shots with 10 or more legs.

The AGA also estimated, using its own tracker, that users under 21 had wagered $9.5 billion on Kalshi by November 2. Kalshi accepts traders from age 18.

New York bars sports betting under 21. An earlier estimate was lower: a CNN analysis in August put trading by 18- to 20-year-olds on Kalshi at $5.4 billion for the year to that point.

Kalshi appealed after a federal judge in July declined to stop New York from enforcing its gambling law, and the Second Circuit refused it an injunction pending appeal on November 3. In a separate lawsuit, New York is seeking at least $36 billion from the exchange.