Analysis · Blog
The Insane Rise of Prediction Market Trading Volumes
Record volume, combination contracts, and what the headline numbers do and do not measure.
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Kalshi recorded $98.15 billion in trading volume in October 2026, more than 22 times its October 2025 figure. But the most revealing number isn't the record itself.
Of that total, $66.78 billion came from combination contracts, which allow traders to bundle multiple outcomes into a single position. According to TickerTracker's historical trading records, these contracts accounted for 68% of Kalshi's October volume.
That raises a question about the prediction-market boom: How much of the extraordinary growth reflects more people trading, and how much comes from the products they're trading?
Sports contracts have become a major source of activity, regulated US exchanges have expanded, and professional traders are playing an increasingly visible role.
From Election Spikes to an Industry Trading Every Day
Prediction markets first attracted widespread attention during the 2024 US presidential election.
Combined monthly trading volume on Kalshi and Polymarket reached approximately $4.74 billion in November 2024, according to Pew Research Center's analysis of The Block's data.
The excitement faded afterward. By February 2025, monthly volume had fallen to $1.72 billion.
Rather than relying on another presidential election, prediction markets began attracting activity through sporting events, cryptocurrency prices and shorter-duration contracts.
Kalshi's historical figures illustrate the transformation.
| Reporting period | Kalshi trading volume |
|---|---|
| Full-year 2025 | $24.06 billion |
| January–October 2025 | $11.67 billion |
| January–October 2026 | $338.85 billion |
| October 2025 | $4.40 billion |
| October 2026 | $98.15 billion |
Source: Our calculations using TickerTracker's monthly Kalshi records. Figures measure contract face-value volume.
Show the numbers
| Month | Volume |
|---|---|
| Jul 2024 | $0.81B |
| Nov 2024 | $4.74B |
| Feb 2025 | $1.72B |
| Jul 2025 | $2.02B |
| Jan 2026 | $17.49B |
| Mar 2026 | $24.27B |
| May 2026 | $25.66B |
| Jun 2026 | $47.75B |
| Jul 2026 | $52.99B |
A separate comparison from Pew Research Center shows combined Kalshi and Polymarket volume rising from $810 million in July 2024 to $2.02 billion in July 2025 and $52.99 billion in July 2026. That's roughly 26 times the previous year's figure.
Kalshi's January–October 2026 volume was approximately 29 times the equivalent period in 2025, representing growth of roughly 2,805%.
One of the biggest jumps came between May and June 2026, when Kalshi's monthly volume rose from $17.91 billion to $33 billion, an increase of approximately 84%. Growth wasn't uninterrupted, however. Volume slipped slightly between July and August before accelerating again in September and October.
The longer historical picture also has limitations. Comparable early-2024 exchange data remains incomplete, and different providers measure trading activity differently.
For the broader figures covering 2024's election surge and the first half of 2026, CryptoCasino.Report’s Prediction Market Statistics page provides additional context.
Kalshi Leads Trading Volume as Polymarket Expands in the US
Kalshi entered the market through the US regulatory system. Polymarket originally developed its international business using blockchain infrastructure before establishing a separate federally regulated US exchange.
Kalshi's share of combined Kalshi and Polymarket trading volume rose from 53.5% in March 2026 to 75.7% in July, largely reflecting increased sports trading.
March 2026
July 2026
DeFi Rate's exchange-volume tracker estimates that Kalshi accounted for 75.7% of volume across its covered exchanges in October 2026.
That is not a measure of every prediction market worldwide, but it demonstrates Kalshi's position among the tracked venues.
According to DeFi Rate's prediction market tracker, Polymarket's US exchange recorded approximately $14.9 billion in trading volume in October 2026, compared with roughly $5.3 billion on its international platform.
The US exchange therefore accounted for approximately 74% of Polymarket's combined volume that month, highlighting the importance of its regulated US business.
Competition is also emerging beyond the two market leaders. According to DeFi Rate, DraftKings Predictions recorded approximately $4.5 billion in contract volume in October 2026, while Novig generated around $3.3 billion. Both remain considerably smaller than Kalshi, but their trading activity shows that the market is expanding beyond its original leaders.
Trading figures must use consistent definitions and reporting periods. They can also double-count activity when broker-reported trades are added to the volume of the underlying exchange.
Sports Created the Momentum, but Combination Contracts Accelerated It
Unlike presidential elections, which occur on fixed schedules, sporting events provide a continuous stream of opportunities to trade.
Kalshi's founders acknowledged the importance of this business during an April 2026 interview with Axios.
Approximately 70% of Kalshi's March trading volume involved sports, according to Axios. Co-founders Tarek Mansour and Luana Lopes Lara explained that sports trading helped support engagement, revenue and liquidity.
That is the company's explanation for part of its strategy, not independent proof of what caused every increase in volume.
The 2026 FIFA World Cup offered a clearer example of event-driven demand.
Dune's World Cup trading analysis identified approximately $19 billion in tournament-related notional volume across Kalshi and Polymarket through July 20.
But by October, another category had become the biggest contributor to Kalshi's growth.
Often called parlays, these contracts can combine sporting events or other conditions, creating lower-probability outcomes that often trade at lower prices.
The monthly figures show how quickly they expanded.
Combination contracts
Standard sports
Cryptocurrency
Between September and October, Kalshi's overall trading volume increased by $37.30 billion.
Combination contracts contributed $31.31 billion of that increase, approximately 84%.
Cryptocurrency trading also accelerated. According to Pew Research Center's category data, Kalshi's crypto volume rose from $1.88 billion in May 2026 to $6.10 billion in July. Economic events attracted smaller bursts of activity. Kalshi's economics category recorded $20.46 million on September 17, 2025, its largest daily volume, coinciding with the Federal Reserve's interest-rate cut. These were meaningful movements, although combination contracts accounted for much more of Kalshi's recent growth.
How Combination Contracts Make Trading Volume Look Enormous
An independent investigation by Predicted, published in August 2026, examined how combination contracts affect prediction-market volume.
The researchers found that Kalshi's combination contracts had generated $46.56 billion in notional volume since their launch, but only $3.97 billion in cash traded over the period examined.
For every dollar exchanged, approximately $11.70 appeared in reported contract face-value volume.
For Kalshi's other contracts, the corresponding figure was approximately $2.30.
The difference comes from how event contracts are priced.
A contract might settle at $1 if every required event happens, but cost only a few cents when purchased.
A trader buying 1,000 contracts at five cents each pays $50 before fees. Yet that execution contributes $1,000 in contract face-value volume.
This doesn't mean the trading activity is artificial. The contracts are genuinely being bought and sold. It means the face-value measure answers a different question from how much cash traders exchanged.
DeFi Rate's October 2026 calculations report approximately $97.8 billion in Kalshi contract volume, compared with $22 billion measured using execution prices.
That cash-execution value was only about 22.5% of the face-value total.
Neither measure represents the amount of new money deposited. Existing funds can be reused for subsequent trades.
Trading volume also shouldn't be confused with open interest, the value or quantity of outstanding positions; trade count, the number of executions; or revenue, the income the platform earns.
These distinctions help explain why record volume doesn't automatically translate into equally dramatic business growth.
A similar measurement problem exists in crypto gambling, where reported deposits and estimated revenue represent different things. Our Crypto Gambling Statistics report examines that distinction using on-chain data.
Are More People Trading, or Are Existing Traders More Active?
A March 2026 study by blockchain analytics company TRM Labs estimated that monthly unique wallets across four on-chain prediction-market platforms reached approximately 840,000 by February 2026, more than tripling over the preceding six months.
That suggests the expansion wasn't solely driven by existing participants trading larger amounts.
However, wallets aren't necessarily unique people. One individual can control multiple addresses, while traditional exchanges such as Kalshi use accounts rather than public blockchain wallets.
Polymarket founder Shayne Coplan acknowledged another distinction during his November 2025 interview with CBS's 60 Minutes.
He estimated that tens of millions of people viewed Polymarket's probabilities, while the number actually trading was in the mid-hundreds of thousands.
These were company-reported estimates, not independently audited user figures. Nevertheless, they highlight why audience reach and trading adoption should be measured separately.
Concentrated Liquidity Among Specialized Participants
In a September 2026 study of Polymarket International, Dune analyzed trading behavior between March and August.
The platform recorded 966,750 active wallets during June–August. Yet just 30 addresses supplied 21.7% of resting liquidity, while ten pair-arbitrage addresses accounted for 8.4% of taker-side trading flow.
Those percentages measure different activities and cannot be added together.
The findings indicate that substantial trading activity can be concentrated among relatively few specialized participants, even on platforms with large numbers of active wallets.
Professional traders and market makers contribute liquidity, help execute orders and sometimes exploit differences between related contract prices.
Their activity is a legitimate part of the market. But it does not necessarily mean that more individuals are using prediction markets to forecast events.
Dune also found that Polymarket International's taker notional volume declined 13% between March–May and June–August 2026, despite the World Cup increasing sports-related activity.
Institutional Expansion Offers Opportunity
Prediction markets are increasingly attracting established financial institutions.
In October 2025, Intercontinental Exchange announced an investment of up to $2 billion in Polymarket, alongside plans to distribute prediction-market data to institutional customers.
In February 2026, Tradeweb announced a strategic partnership with Kalshi, intended to expand institutional access to event-market information and trading infrastructure.
These arrangements point toward possible uses beyond retail speculation, including economic forecasting, risk management and financial research.
In its October 29, 2026 announcement, Kalshi reported approximately 500 active entities in September and said that entities excluding market makers accounted for around 25% of total exchange trading volume. These company-reported figures suggest growing institutional involvement, although they do not provide an independently verified breakdown of institutional trading.
The company also reported more than 30 million accounts created and over $1 trillion in annualized trading volume across its broader business.
Accounts created aren't monthly active users. Annualized volume isn't a completed year's trading total, and Kalshi's broader business includes products beyond prediction markets.
Navigating Regulatory Roadblocks
In June 2026, the Commodity Futures Trading Commission proposed amendments concerning how certain event contracts, including those potentially involving gaming, should be evaluated.
Then, on September 25, the Sixth Circuit Court of Appeals ruled that Kalshi had not established that federal derivatives regulation prevented Ohio and Tennessee from applying the state gambling laws at issue to its sports contracts.
That decision did not settle every regulatory dispute, but it illustrated the legal uncertainty surrounding a major source of industry trading activity.
Further restrictions could affect market access and volume. Clearer rules, broader distribution and institutional adoption could support expansion elsewhere.
The Growth Is Real. Its Sustainability Is Still Unproven.
Combination contracts accounted for 68% of Kalshi's October 2026 volume, while actual cash-execution values remained substantially below headline contract face-value totals. Independent research also revealed concentrated liquidity and declining activity in parts of Polymarket International.
These findings don't invalidate the industry's growth. They show why trading volume alone cannot establish how widely prediction markets have been adopted or how sustainable their expansion will be.
The industry no longer has to wait for the next presidential election to generate substantial trading volume. The real test is whether activity continues across different categories after major sporting events end and demand for combination contracts changes.
Prediction markets have demonstrated that they can generate extraordinary trading volumes. Whether those numbers reflect the foundation of a lasting financial industry remains an open question.