IEM Cologne drove 63% of all Kalshi esports betting volume in the week of June 7–13

The week of June 7–13 saw $66.2 million in esports prediction market contracts on Kalshi, and the story behind what drove that number was never really in doubt. Counter-Strike 2 was responsible for nearly two-thirds of all activity, with IEM Cologne at the epicentre of all esports trading activity.

That $66.2M figure is worth comparing to the $36.18M generated the previous week (June 1–7), though with a caveat: both datasets include June 7th, so they aren’t perfectly consecutive. With that noted, the directional shift is significant regardless: more than $30M in additional volume during a period when IEM Cologne was entering the more consequential stages of the tournament.

CS2’s 63.1% share is impressive, regardless. In a week that also featured the LCK, the LEC, VALORANT Masters London, the CDL regular season, and Rainbow Six action in North America and Europe, CS2 still claimed nearly all available attention. The reason, one would suggest, is straightforward: IEM Cologne is the premier CS2 event of the summer and is up there with the most prestigious esports events.

Further, as explored in our game-by-game breakdown of the previous week, CS2 has a more deeply embedded gambling culture than any other esport. This is through years of skin betting, gambling sponsorships, and an audience that is simply more comfortable with the idea of prediction markets, betting exchanges and trading and/or wagering. A large competition, paired with greater appetite to trade creates liquidity. Another point to consider is that there’s a chance that sportsbooks use the Kalshi liquidity to hedge their exposure

The IEM Cologne Effect

IEM Cologne is not just any Counter-Strike tournament. The 18,500-capacity LANXESS arena in Cologne is affectionately dubbed the “cathedral of Counter-Strike” by fans and is one of the most notable fixtures in the CS calendar. With the absence of a World Championship, or an event akin to The International, the Major circuit is as big as events get in CS. It’s fair to say Cologne is up there with the most iconic esports events out there, from a reputational standpoint.

The Spirit vs. 9z match winner market alone generated over $2.56M in contracts across both sides making it the single most traded matchup of the entire esports week across every game. When drilling deeper into the data, the fixture generated another $330,000 in map betting and the over/under markets too.

The Tournament Winner Markets

The tournament winner market for IEM Cologne captured $449,015 in contracts across the full field during the week. In this case, context is pretty important as the snapshot we’ve taken for seven days doesn’t tell the story.

The market opened on May 31st, meaning this snapshot captures a week of a mammoth event, but it is a good gauge of how warm traders are feeling about each team’s chances relative to their implied probabilities.

From the data we’ve pulled, Spirit led contract volume for the outright winner market with 22.5%, and Vitality was second in 16.8%. Falcons, the team that will meet Vitality in the single elimination playoffs, attracted 11.0%, and that individual match-up is sure to see significant interest when it comes.

Spirit Building Momentum, Vitality in the Picture

Spirit’s dominance of match-level contract volume during the week perhaps point to an assuredness in Vitality’s progression as the outright favorite that meant match-specific trading on their matches failed to generate too much interest.

In the period, however, Vitality did attract a 16.8% share of the tournament winner contracts during the same period and maintains its position as tournament favorite on Kalshi. The data we review post tournament will go to show how the activity changed before, during and after the playoffs.

Valorant: A Competitive Market But Just Not Quite Counter-Strike

VALORANT Masters London is running concurrently, and the overall market for the week seems to be more all over the place. Where IEM Cologne’s winner market had a clear top two — Spirit at 22.5% and Vitality at 16.8% — Masters London was almost flat across its top five. EDward Gaming led with 17.2%, but XLG Esports (12.2%), Paper Rex (11.9%), and NRG (11.6%) were all within a few percentage points.

It also reflects the relative scale gap from VALORANT to Counter-Strike. The entire VALORANT tournament winner market produced $65,354 in contracts across all teams — roughly 14.5% of what just the top CS2 match market (Spirit vs. 9z) generated on its own. Valorant’s 9.9% overall share of weekly volume is healthy, and match-level trading in the game was robust, but the tournament-winner format has yet to attract the depth of engagement that CS2’s equivalent generates.

The Rest of the Field in Esports Prediction Markets

League of Legends held its expected second-place position at 22.0% of weekly volume, driven by the LCK. T1 vs. Hanwha Life and the KT Rolster vs. Gen.G series were the two busiest individual markets, alongside the LEC and LPL. It is worth noting that LoL’s $14.56M came without a major tournament final in the week; this is baseline League activity driven by regional leagues. When we reach MSI and other upcoming notable events then we may well see it challenge the status quo.

Call of Duty and Rainbow Six each accounted for just over 2% of total volume, which understates the quality of individual match markets in both games. The 100 Thieves vs. Wildcard Gaming R6 matchup drew $233K in combined contracts, and OpTic Texas vs. Paris Gentle Mates pulled $116K in CoD. Both these numbers are a decent amount of volume and show that there’s still interest when the big names are wheeled out in Call of Duty. However, they are frankly dwarfed by the IEM Cologne effect.

Editor’s Data note: All figures represent prediction market contracts traded on Kalshi during the period June 7–13, 2026, where 1 contract = $1. Contract volume reflects market activity and trader sentiment; it does not directly represent odds or implied probability without additional calculation. Rolling 7-day summary (Jun 11–17): $57.0M esports contracts, 861K trades. Previous period (Jun 1–7): $36.18M — note that both datasets include June 7th, so are not perfectly consecutive; from this week onwards the reporting window runs Sunday to Saturday.