Kalshi and Polymarket record $45 billion combined volume in June as World Cup boosts activity

Prediction markets operated by Kalshi and Polymarket witnessed a dramatic jump in trading activity last month, as the FIFA World Cup 2026 continues to fuel global participation in event-based speculation markets.

Data from The Block’s analytics dashboard shows that Kalshi, Polymarket, and Polymarket US collectively processed $44.8 billion in trading volume during June. This represents a strong 75% increase compared to May’s $25.66 billion.

Kalshi Leads Monthly Growth Among Platforms

Among all platforms, Kalshi recorded the most significant expansion in activity. Its monthly volume surged by 87.4%, reaching $31.5 billion in June, up from $16.81 billion in the previous month.

This sharp rise positions Kalshi as the dominant contributor to the overall growth in the prediction market sector during the period.

Polymarket Sees Mixed Performance Across Regions

On the other hand, Polymarket showed more varied performance depending on jurisdiction. Its global platform recorded $10.26 billion in trading volume, reflecting a 45% monthly increase from $7.08 billion in May.

However, this follows a period of gradual decline between March and May, suggesting a recovery in momentum after several months of weakening activity.

Meanwhile, Polymarket’s U.S.-regulated arm continued to expand steadily, posting $3.04 billion in volume, up from $1.77 billion in May.

World Cup Betting Activity Fuels Market Expansion

A major driver behind this surge has been heightened interest in FIFA World Cup 2026, which began on June 11. The tournament has significantly boosted engagement across prediction markets.

On Kalshi, the “World Cup Winner” market alone has attracted over $832 million in wagers, with France emerging as the most favored outcome among participants, accounting for roughly 35% of bets.

Similarly, on Polymarket, individual match contracts are generating between $500,000 and $2 million in daily trading volume. The tournament is scheduled to conclude on July 19.

Regulatory Scrutiny and Legal Challenges in the U.S.

Despite the rapid expansion, both platforms are facing increasing legal scrutiny in the United States. More than a dozen state regulators have initiated actions against Kalshi and Polymarket, alleging that their sports-related contracts may constitute unlicensed gambling activities.

In response, both companies, along with the U.S. Commodity Futures Trading Commission, maintain that federal oversight permits such markets and supersedes state-level restrictions.

Broader Market Implications Beyond the World Cup

The recent surge in prediction market volumes highlights how major global sporting events can rapidly reshape liquidity patterns across emerging financial platforms. While the FIFA World Cup 2026 has clearly acted as a catalyst for user engagement and capital inflows, the sustainability of this growth remains uncertain once the tournament concludes.

At the same time, the intensifying regulatory friction in the U.S. introduces a structural risk that could redefine how prediction markets operate, scale, and position themselves within the broader financial ecosystem.