August became the first month in the past year when the total trading volume on leading prediction platforms — Kalshi, Polymarket, and its U.S. segment Polymarket US — showed a noticeable decline. The figure dropped by 14.5%, settling at $45.33 billion. This is a landmark event that breaks the trend of continuous growth observed since August 2025.
The volume distribution confirms Kalshi's dominance, accounting for $37.17 billion. Polymarket, along with the regulated platform for U.S. clients, generated only $8.16 billion, highlighting the persistent liquidity gap between these players. However, even the leader has seen a cooling off.
It is worth noting that the current correction occurred after an extremely hot summer period, when trader activity was fueled by the FIFA World Cup. A tournament of this scale traditionally acts as a powerful catalyst for bets on sports outcomes, artificially inflating metrics. Now that the event-driven backdrop has faded, the market is returning to more organic levels.
In my analysis, this does not look like an alarming signal, but rather a natural normalization. Prediction markets are still in a phase of institutional recognition, and short-term dips after peak events are standard practice. What matters much more is whether Kalshi can retain user interest regardless of the sports calendar, especially ahead of political cycles that historically generate a steady influx of capital.