Parlays Push Kalshi Past $3.9 Billion in a Day, Twice in a Weekend

Combos Supplied Most of the Growth

Kalshi’s daily market data, which runs on U.S. Eastern days, shows $3.91 billion in notional volume on Saturday, Oct. 10, and $3.96 billion on Sunday, Oct. 11, both above the previous high of $3.68 billion set on Sunday, Oct. 4. Notional volume counts each contract at its full $1 payout, which the buyer and seller fund between them according to the price.

Both days were about 61% above the corresponding days of the NFL’s opening weekend, when Kalshi set consecutive daily records at under $2.5 billion each. It has now passed $3 billion on seven days, all of them since Sept. 19.

Combos, Kalshi’s parlay-style contracts that bundle several outcomes into one, accounted for $2.80 billion of Saturday’s volume, or 71.6%, and $2.75 billion of Sunday’s, or 69.4%. They also supplied most of the week-over-week growth. Saturday’s total was $459 million higher than on Oct. 3, with combos up $400 million, and Sunday’s was $279 million higher than on Oct. 4, with combos up $218 million.

Much of that combo volume came from long-shot parlays. About 1.9 billion of Saturday’s 2.8 billion combo contracts, and 1.6 billion of Sunday’s 2.75 billion, were in combos whose Yes side never traded at 1 cent or more that day. In those trades, the parlay buyer paid a fraction of a cent per contract and the other side put up the rest of the $1. The rise in those contracts alone accounted for about three-quarters of Saturday’s increase over the previous Saturday and 86% of Sunday’s. One 13-leg combo on NFL winners traded 12.1 million contracts on Sunday at Yes prices between 0.01 cent and 0.44 cent. Parlay buyers paid about $13,800 for them, and the other side put up about $12.1 million. The parlay lost.

Outside combos, college football markets traded $428 million on Saturday, against $17 million for the NFL, which had no games that day. On Sunday, NFL markets traded $572 million, up 18% from a week earlier, and college football $21 million. Kalshi’s 15-minute bitcoin markets traded $229 million on Saturday and $234 million on Sunday, the most of any non-combo series after college football and NFL game markets, respectively.

Separately, Kalshi told the CFTC in a Sept. 28 filing that it would end its Volume Incentive Program no earlier than Oct. 13, nearly a year before its scheduled Oct. 1, 2027, end. The program pays traders a share of per-market rewards, capped at half a cent per contract. For event contracts, only order-book trades at prices between 3 and 97 cents qualify, so the sub-cent combos behind most of the weekend’s growth did not. The filing gave no reason, and it came as the CFTC was reviewing prediction market incentive programs, after an August staff advisory warned that volume-based rewards with steep tiers or threshold bonuses can encourage wash trading.