Prediction Markets Experience Unprecedented Surge: Global Trading Volumes Double Between May and July 2026

The global landscape of prediction markets has entered a period of extraordinary financial expansion. According to a comprehensive Pew Research Center analysis utilizing digital asset data from The Block, the combined monthly global trading volume on Kalshi and Polymarket—the industry’s two dominant platforms—more than doubled in a remarkably short window. Trading activity skyrocketed from $26 billion in May 2026 to $53 billion by July 2026.

This dramatic escalation marks a transformative milestone for decentralized and regulated event-contract platforms. What was once a niche ecosystem dominated primarily by political forecasting during election cycles has rapidly evolved into a mainstream financial venue. Driving this monumental growth is a massive influx of sports-related wagering, shifting market dominance dynamics, and shifting regulatory frameworks across the United States and international jurisdictions.

Chronology of Growth: From Election Hype to Summer Sports Mania

To understand the trajectory of prediction markets, analysts look back at the dramatic fluctuations in trading volume over the past two years.

• Late 2024 (The Election Peak): Prediction markets first captured mainstream public attention during the fall of 2024, catalyzed by the U.S. presidential election. In October and November 2024, political contracts dominated the platforms, driving monthly volumes to $4.5 billion and $4.7 billion, respectively. During this period, political markets accounted for roughly 90% of Kalshi’s volume and 65% of Polymarket’s.
• Early 2025 (Post-Election Lull): As the political cycle concluded, trading volumes experienced a predictable cooldown. Monthly totals hovered between $1.7 billion and $2.1 billion through the first half of 2025.
• Late 2025 (The Resurgence Begins): Volume began climbing steadily in the autumn of 2025, hitting $8.5 billion in October and $12 billion in December. This rebound was heavily fueled by the return of professional football and the launch of CFTC-regulated Polymarket US in late 2025.
• Early to Mid-2026 (The Explosive Doubling): By January 2026, monthly volumes crossed the $17 billion threshold and climbed steadily to $25.1 billion in April and $25.7 billion in May. Then came the historic acceleration: combined trading volumes nearly doubled over a two-month span, jumping to $47.7 billion in June and peaking at $53 billion in July 2026.

Despite a slight seasonal cooling in August 2026—which still closed at a robust $47 billion—preliminary September data indicates that volumes are once again ticking upward with the commencement of the new football season.

Supporting Data: Sports Take the Crown

The core engine powering the 2026 volume explosion is sports betting. Coinciding with major international fixtures—most notably the FIFA World Cup in June and July 2026—sports trading reached staggering heights.

During June and July alone, sports trading topped $58 billion on Kalshi and neared $22 billion on Polymarket.

Pew Research Center’s findings underscore that sports traders consistently place a higher volume of individual trades than users focused on economics, pop culture, or politics. On both Kalshi and Polymarket, sports has firmly unseated politics as the primary category by a wide margin.

Furthermore, auxiliary asset classes have expanded. Cryptocurrency-based prediction contracts on Kalshi have seen steady growth, culminating in $6 billion in trading volume in July alone, establishing crypto as Kalshi’s second-largest vertical.

Platform Divergence: Kalshi’s Ascent and Polymarket’s Evolution

While both platforms share an affinity for sports-driven growth, their internal metrics and structural developments reveal distinct institutional paths.

1. Kalshi’s Rapid Acceleration

As recently as March 2026, Kalshi and Polymarket each commanded roughly a 50% market share of the prediction market space. Since then, however, Kalshi’s trading volume has accelerated at a significantly steeper rate. By July 2026, Kalshi’s monthly volume surged past $31 billion, outpacing its rival. This growth was buoyed by massive sports contract offerings and a flourishing cryptocurrency contract sector.

2. The Return of Polymarket US

Polymarket, which historically operated as an international, decentralized platform that faced regulatory scrutiny for allowing U.S.-based users to trade without local licensing, entered a new chapter in late 2025. Following approval from the Commodity Futures Trading Commission (CFTC), the platform launched Polymarket US. This regulated domestic arm has experienced exponential adoption: its share of Polymarket’s total trading volume grew from a modest 4% in January 2026 to 39% by July 2026.

3. The Curious Case of Politics

While political contracts dominated headlines in late 2024, they have taken a back seat to sports in 2026. Monthly political trading volume on Polymarket has averaged around $2 billion since January 2026, while on Kalshi, it has consistently remained below $300 million outside of major election cycles.

Official Responses and Regulatory Scrutiny

The explosive growth of prediction markets has not occurred without friction. The sheer scale of sports prediction contracts—rivaling the legal sports betting industry—has triggered alarm bells among federal and state regulators.

To put the scale into perspective, Americans legally wagered roughly $40 billion on traditional U.S. sportsbooks in the first quarter of 2026. This figure is roughly comparable to the combined global prediction market trading volume on sports over the same timeframe.

Because prediction markets offer binary event contracts ($0 to $1 payouts based on game outcomes), critics and traditional gaming operators argue that these platforms are effectively operating as nationwide sportsbooks—often bypassing the patchwork of state-level sports betting regulations and tax structures.

Federal lawmakers have taken notice. Bipartisan legislation has been introduced in Congress—such as a bill introduced by lawmakers including Senator Curtis—aimed specifically at banning sports prediction market contracts. Regulators argue that without strict geographic and age verification protocols mirroring state-regulated sportsbooks, these platforms undermine local gaming laws and consumer protection standards.

Conversely, platform defenders and financial technologists maintain that prediction markets provide valuable, crowdsourced probabilities on real-world events that traditional sportsbooks cannot replicate, offering superior price discovery mechanisms.

Broader Implications for Finance, Gambling, and Society

The normalization of high-frequency event contracting carries profound implications across multiple sectors:

• The Convergence of Gambling and Finance: The boundary lines between speculative financial trading, crypto derivatives, and sports gambling are blurring. Prediction markets offer retail users a gamified financial experience that feels increasingly indistinguishable from sports betting, yet operates under financial regulatory frameworks rather than state gaming commissions.
• Regulatory Compliance and State Authority: With more than half of U.S. states strictly restricting or outright banning betting on elections and certain athletic events, the national scale of platforms like Kalshi and Polymarket US creates jurisdictional headaches. Federal regulators like the CFTC face mounting pressure to harmonize rules between traditional financial derivatives and digital event contracts.
• Public Perception: Previous Pew Research Center studies indicate a growing public skepticism toward the societal impacts of legal sports betting. As prediction markets normalize gambling-like behavior under the guise of financial forecasting, public policy debates regarding addiction, financial literacy, and consumer protection will likely intensify.

As prediction markets transition from temporary novelties fueled by political cycles and global soccer tournaments into permanent fixtures of the digital asset economy, their long-term survival will depend heavily on how regulators navigate the blurry gray area between finance and sports gambling.