August became the first month in the past year when leading prediction market platforms recorded a decline in activity. The combined trading volume on Kalshi, Polymarket, and the specialized American platform Polymarket US fell by 14.5% to $45.33 billion. This marks a notable reversal after a prolonged period of growth that had lasted since August 2025.
The distribution of volumes shows Kalshi's continued dominance: this platform accounted for $37.17 billion, representing more than 80% of the total. At the same time, Polymarket together with its US segment generated only $8.16 billion. This disparity reflects structural changes in the competitive landscape: Kalshi is steadily strengthening its position in the US institutional and retail markets, while Polymarket faces more stringent regulatory and operational challenges.
Notably, the decline came right after a summer surge in activity driven by the FIFA World Cup. The tournament traditionally generates significant interest in betting on match outcomes, but the effect proved short-lived. It seems that the market has become saturated with sporting events, and investors are now shifting focus to political and macroeconomic themes, which require different growth drivers.
My analysis shows that the current correction is not a sign of stagnation, but rather a natural pause after extreme hype. Prediction markets remain a highly volatile segment, and August's figures may signal the beginning of consolidation. In the coming months, the key factor will be the platforms' ability to attract liquidity outside major sporting events—for example, through expanding their lineup of political contracts ahead of election cycles.