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- Kalshi processed a massive $18.37 billion in trading volume during the week of September 28 to October 4, continuing a sharp 102% six-week surge that heavily outpaced rival Polymarket US, according to new market data reported by DeFi Rate.
- While Kalshi’s broader “Exotics” category accounted for over 64% of the weekly activity, the single largest individual markets on the platform were massive multi-leg sports combos, led by a 10-leg NFL contract involving player statistics and team winners that generated $117.16 million in volume on its own.
Kalshi handled $18.37 billion in volume for Sept. 28 through Oct. 4, up 17.28% from the prior UTC week, according to market data reported by DeFi Rate.
The weekly total was the highest figure cited in the report and extended a sharp recent climb for the U.S. prediction market operator. Over the six weeks from the week ending Aug. 23 to the week ending Oct. 4, Kalshi’s weekly volume increased 102.65%, from $9.06 billion to $18.37 billion.
Exotics accounted for most of Kalshi’s weekly activity
The biggest contributor was Kalshi’s identified Exotics category, which reached $11.82 billion, up 24.87% week over week. That category alone represented 64.34% of Kalshi’s total volume for the period.
Kalshi’s identified Sports category generated $3.64 billion, up 1.31%. Within sports, Football-tagged series produced $1.37 billion, up 7.20%. Soccer-tagged series rose 40.73% to $452.63 million, while Baseball-tagged series fell 32.59% to $362.07 million.
The report also showed gains outside sports. Kalshi’s identified Crypto category reached $2.42 billion, up 7.37%, with BTC-tagged series at $2.13 billion and ETH-tagged series at $118.90 million. The identified Financials category climbed to $83.25 million, a 646.26% increase from the previous week. Commodities rose to $274.64 million.
Large combo sports markets led individual contracts
The largest individual market on Kalshi during the week was a 10-leg NFL combo involving player statistics and team winners, which generated $117.16 million in volume. The second-largest was a 10-leg college football combo covering multiple games and point spreads at $102.68 million.
A four-leg MLB player performance combo involving Matt Olson, Mookie Betts, Jonathan Aranda, and Manny Machado produced $36.19 million. DeFi Rate noted that “a combo is one market containing several conditions.”
The report also said the historical week ending Sept. 27 recorded 88,115,678 trades. Kalshi’s category mapping left $1.14 million of current-week volume and $2.07 million of prior-week volume outside identified categories.
Polymarket results were mixed across reporting windows
By comparison, Polymarket US reported $2.71 billion in volume for the Sept. 28-Oct. 4 business-date week, down 4.41% from the prior week. Separately, Polymarket’s Eastern-week measure recorded $519.01 million in dollar volume, up 6.26%.
The week-to-week split suggests momentum differed depending on the reporting window, while Kalshi’s gains were driven most clearly by Exotics and large multi-leg sports markets. The next question for the sector is whether Kalshi can maintain volume near the $18 billion mark in the weeks ahead.
Source: As reported by news.google.com.
