Polymarket and Kalshi Top $150 Billion in Cumulative Volume as April Trading Hits Record

Prediction markets let traders buy contracts tied to outcomes ranging from elections and policy decisions to economic events. Trading volume is a key gauge of participation, liquidity and momentum across the sector. Kalshi and Polymarket are closely watched as two leading venues, making their combined monthly activity a useful indicator of whether the recent expansion in event-based trading is continuing or beginning to cool.

In August, combined trading volume at Kalshi and Polymarket, including Polymarket’s US platform, fell 14.5% from July, or roughly 15%, marking the first monthly decline in a year. Kalshi recorded $37.17 billion in volume, while Polymarket and its US venue generated a combined $8.16 billion. Total activity therefore reached about $45.33 billion, signaling a pause after a year-long run without a monthly contraction.

Kalshi and Polymarket allow traders to buy contracts tied to outcomes in politics, sports and other real-world events, with prices serving as market-implied probabilities. Their growing scale underscores prediction markets’ shift from niche wagering products toward a broader financial and consumer category, drawing closer scrutiny of liquidity, market structure and regulation as more users and capital enter the sector.

Combined trading volume at Kalshi and Polymarket exceeded $50.6 billion in July 2026, setting a monthly record as World Cup-related contracts helped drive activity. Polymarket’s US market posted a 54% increase from June, while volume on its main platform fell 26% over the same period. The divergence suggests that fresh demand was concentrated in the regulated US offering and major sports events rather than spread evenly across Polymarket’s operations.

Prediction markets let traders wager on real-world outcomes, making the 2026 FIFA World Cup a major test of the sector’s ability to attract mainstream users. Kalshi and Polymarket now account for more than 95% of the market, cementing a duopoly in which scale, consumer reach and marketing spending increasingly determine which platform converts attention into trading activity.

After the tournament concluded in July 2026, Kalshi reported $54.338 billion in total platform trading volume, 2.6 times Polymarket’s tally. Kalshi also led in app downloads and aggregate trading value, helped by heavy advertising spending. Polymarket continued to draw more website visits, but that traffic did not translate into a volume lead, leaving Kalshi ahead on the industry’s most closely watched commercial measures.

Prediction markets allow users to trade contracts tied to the outcomes of sporting, political and other events, with prices reflecting the market-implied probability of each result. Betting demand generated by the 2026 FIFA World Cup rapidly expanded Kalshi and Polymarket, bringing greater scrutiny to their liquidity, compliance and regulatory disputes across U.S. states.

Kalshi and Polymarket recorded a combined $44.8 billion in trading volume in June 2026, up 75% from May. Kalshi's monthly volume surged 87.4% to a platform record. Polymarket also returned to growth, supported by World Cup enthusiasm and U.S. market demand, though both companies continued to face regulatory challenges from several U.S. state governments.

Polymarket is a prediction-market platform where users trade on the outcomes of political, economic and public events. It has expanded its regulated U.S. operations in recent years. The revenue surge could help support its pursuit of a $15 billion valuation and intensify its competition with regulated rival Kalshi.

By the sixth week after the launch of its U.S. exchange, Polymarket’s projected annualized revenue had exceeded $1 billion, indicating that the new market quickly boosted trading and fee income. Although reports did not disclose the exact launch date or weekly revenue, the milestone has become an important indicator of prediction markets’ accelerating move into the mainstream.

Polymarket uses blockchain to settle event contracts, while Kalshi is an exchange regulated by the U.S. Commodity Futures Trading Commission. Both allow investors to trade on election, economic and sports outcomes. The companies were valued at $9 billion and $11 billion, respectively, at the end of 2025, making them key indicators of whether prediction markets can enter mainstream finance.

The Wall Street Journal reported on March 7 that Polymarket and Kalshi were each in talks to raise funds at valuations of about $20 billion. Their paths subsequently diverged. On May 7, Kalshi completed a $1 billion Series F round led by Coatue at a $22 billion valuation. Polymarket, meanwhile, was reported on April 20 to be seeking $400 million at a $15 billion valuation.

Prediction markets allow users to put money behind their forecasts for political, economic and cultural events, but they have often been viewed as venues for occasional gambling. A report by Bitget Wallet and Polymarket says retail users are increasingly trading frequently, gradually turning such platforms into everyday tools for tracking news trends and market consensus.

Polymarket's monthly trading volume rose to $25.7 billion in early 2026, while its number of active wallets also increased sharply. The figures suggest participation is no longer driven solely by major elections. The report estimates that the prediction market industry could reach $240 billion, signaling that these platforms are rapidly moving into the mainstream.

Polymarket is an onchain prediction market built on Polygon where users trade on the outcomes of political, economic, technology and other events. The platform generates revenue from trading fees. Its revenue surge suggests prediction markets may become a sustainable crypto finance business rather than relying solely on election-driven interest, though regulatory pressure in the United States, Europe and Argentina remains a major risk.

On March 30, 2026, Polymarket expanded taker fees beyond crypto and sports to markets covering finance, politics, economics, culture, weather and technology. DeFiLlama data showed daily fees rising from about $363,000 to more than $1 million on both April 1 and April 2, putting the early annualized estimate at about $338 million. Fees totaled $7.1 million in the first week of the second quarter, accounting for 96.8% of all onchain prediction-market fees.

Prediction markets allow traders to wager real money on event outcomes, making prices a signal of probability and risk. With the Iran war affecting oil prices, national security and crypto assets, Polymarket and Kalshi have become real-time macroeconomic radars. However, the U.S. Commodity Futures Trading Commission strictly limits contracts tied to war, while regulatory and insider-trading risks in offshore markets are also rising.

In the week ended March 1, 2026, geopolitical trading volume on Polymarket jumped to a record $425 million from $164 million the previous week. By March 9, weekly notional trading volume on Polymarket and Kalshi had set fresh records of $2.49 billion and $2.85 billion, respectively. On April 6, Sygnum said professional trading desks had incorporated such markets into their monitoring of macroeconomic risks.

Prediction markets allow participants to wager on the outcomes of political, economic and public events, with prices reflecting the crowd’s assessment of their probabilities. As crypto assets and on-chain settlement expand, these platforms are emerging as a new gauge of market expectations. Polymarket’s lead also underscores the impact of liquidity and pricing power becoming concentrated on a small number of platforms.

An OKX Ventures report said global prediction market open interest topped $1 billion for the first time in February 2026, while total trading volume reached $18.7 billion. Polymarket remained firmly in the lead with a 55% market share. However, capital was heavily concentrated in popular events, while retail sentiment created a clear pricing premium, showing that market efficiency and depth remain uneven despite rapid growth.