Kalshi and Polymarket Volumes Hit Record $50.59B in July on World Cup Surge

Prediction Markets Just Posted Their Biggest Month on Record

Event trading platforms Kalshi and Polymarket closed July with $50.59 billion in combined monthly volume, the highest figure ever recorded for the sector, according to data reported by The Block. The total covers three venues: Kalshi, Polymarket’s main offshore platform, and its newer regulated US arm.

The record represents a 7.8% jump from June’s $46.95 billion, which was itself a milestone month: The Block reported that June volume had surged roughly 75% over May as World Cup fever took hold. Two record months back to back point to a sector compounding fast. While much of the crypto market spent July watching crypto market prices chop sideways, the money flowing into event contracts kept climbing.

Kalshi Extends Its Lead With $37.7 Billion in July

Kalshi remained the clear volume leader, processing $37.7 billion during the month, a 14% increase over June. The CFTC-regulated exchange has now pulled decisively ahead of its rival after trailing Polymarket through early 2026.

That figure means Kalshi alone handled roughly three-quarters of the volume tracked across the three venues in July. Its Spain versus Argentina World Cup final market attracted $1.9 billion on its own, a striking total for a single event contract.

Polymarket’s US Arm Surges While Its Offshore Platform Cools

The Polymarket picture is more split. Its regulated US platform, which removed waitlist restrictions in May and opened to all American users, grew volume 54% month over month to roughly $5 billion. The main offshore platform moved in the opposite direction, falling 26% to $7.9 billion.

Combined, the two Polymarket venues handled $12.9 billion, down from about $14 billion in June. The shift suggests American traders are migrating to the compliant venue now that a legal route exists. One Rutgers statistician has estimated that US traders drove about 30% of the offshore platform’s volume in the year through April 2026.

How Prediction Markets Actually Work

For newcomers, prediction markets are simpler than they sound. Traders buy Yes or No contracts on a specific question, such as whether a team wins a match or whether the Fed cuts rates. Each contract pays out $1 if the outcome happens and nothing if it does not.

The price of a contract floats between zero and $1 and works like a live probability gauge. A Yes contract trading at 70 cents implies the market collectively sees a 70% chance of that outcome. If the event happens, the holder collects $1 per contract; if it does not, the contract expires worthless. Traders can also exit a position early as the odds move rather than waiting for the result, and that constant repositioning is what generates the enormous trading volumes these platforms report.

On Polymarket, positions are typically funded with stablecoins, which is why many traders first buy crypto before placing a trade. Kalshi, by contrast, operates in dollars under CFTC oversight.

The World Cup Delivered the Fireworks

The FIFA World Cup, which ran from June 11 to July 19, was the engine behind the record. Polymarket’s market on the tournament winner drew approximately $4 billion in volume, while Kalshi’s final market added its $1.9 billion haul.

The tournament’s fingerprints are visible in the aftermath too. Open interest across the three platforms, meaning the value of positions still open, fell from around $2 billion at the start of July to $1.2 billion by month’s end as tournament markets settled and paid out.

Can the Boom Survive Regulators and a Quiet Calendar?

Two clouds hang over the sector’s momentum. The first is the sports calendar: with the World Cup finished, August lacks a comparable global event, and volumes could soften until football season and the US midterm election cycle build up.

The second is regulatory. More than a dozen US state regulators have accused both platforms of running unlicensed gambling operations, claims the companies and the CFTC dispute. How those cases resolve may shape whether event contracts remain broadly accessible in every state, and any adverse ruling could dent the growth curve that July’s record sits on.

Speculation Is Finding a New Home in Event Trading

The bigger story is what the record says about where speculative appetite is going. July’s $50.59 billion arrived in a month when Bitcoin struggled to hold its ground and broader crypto sentiment stayed cautious, suggesting event trading is not merely borrowing crypto’s audience but building its own.

Prediction markets began as a crypto-native experiment and now sit at the intersection of finance, sport, and politics. Whether volumes consolidate or cool from here, the sector has crossed a threshold of scale that regulators, exchanges, and anyone following crypto news today can no longer treat as a niche. The next test is proving the demand persists when there is no tournament to trade.