The second quarter of 2026 was historic for prediction markets: total transaction volume reached $109 billion. This marks the fourth consecutive quarter of growth, and in my assessment, this segment is firmly establishing itself as one of the fastest-growing categories in the crypto industry.
Analytics show that volume grew by 39% compared to the first quarter, and on an annualized basis, the figure increased 18-fold. The key conclusion I draw from this data is that the market is no longer just about a simple battle for users — it is clearly dividing into thematic verticals, each dictating its own rules of the game.
Market Structure: Who Leads and Why
Total open interest (OI) in prediction markets reached $1.8 billion by the end of June. The figure grew by 54% over the month, largely due to the start of the 2026 FIFA World Cup in the United States, Canada, and Mexico.
The OI structure has become more diversified. For the first time, the Kalshi platform took the lead in this metric, overtaking Polymarket after months of intense competition. However, Polymarket still maintains a significant lead over other participants, even despite a decline in its own OI.
The dynamics of weekly trading volumes are particularly telling. Excluding sports markets, activity accelerated noticeably: weekly volume reached $3.1 billion, of which Kalshi accounted for $2.6 billion and Polymarket only $492 million. Thus, Kalshi controls over 80% of this segment.
My analysis shows that Kalshi's leadership is not due to displacing Polymarket per se, but rather to capturing the highest-speed, most speculative part of the market. This indicates rapid position rotation and an active flow of short-term capital.
Platform Specialization and Investor Interest
In crypto prediction markets, the shift toward Kalshi was most pronounced — the platform captured about 42% of the segment from Polymarket. Meanwhile, Polymarket retains its position as a "more established crypto-native platform."
Political markets, on the other hand, remain Polymarket's stronghold. It accounted for about 96% of all trading in this segment during the quarter. Trading volume in political markets reached $5.7 billion, of which $5.5 billion came from Polymarket, though this is still below the peak of the fourth quarter of 2024.
World Cup markets showed explosive growth and were more balanced. Kalshi leads with a volume of $2.8 billion, but Polymarket holds second place with $1.8 billion. Since the start of the tournament, daily volume in prediction markets has increased by approximately 75%.
Investors also confirm interest in the segment. In the first half of 2026, prediction markets became the most funded crypto category, receiving $1.85 billion, ahead of exchanges ($1.57 billion) and AI ($1 billion).
My expert opinion: Prediction markets are passing the point of no return. Investors are increasingly viewing the segment not as a niche direction but as a major financial infrastructure. The quarter's outcome was a clear division of the market into verticals, where leadership is determined not by brand strength but by liquidity depth and market type. Polymarket remains the king of politics, but Kalshi is capturing sports and high-frequency trading. Watching this duopoly will be extremely interesting.