Prediction markets hit record $50.6B July volume
Prediction markets recorded $50.59 billion in combined monthly trading volume in July, setting a new high across Kalshi, Polymarket and Polymarket US, according to data published on Aug. 3.
Summary
- Prediction markets generated $50.6 billion in July volume, rising 7.8% from June’s previous combined total.
- Kalshi led at $37.7 billion; Polymarket US volume climbed 54% to $5 billion during July.
- Open interest fell to $1.2 billion after the World Cup ended, signaling weaker post-tournament activity.
The total rose 7.8% from the dashboard’s revised June figure of $46.95 billion. Kalshi remained the largest venue with $37.7 billion, while Polymarket’s international and U.S. platforms generated a combined $12.9 billion. The figures measure taker notional volume rather than exchange revenue or money deposited by customers.
Prediction market volume reaches a new monthly record
Kalshi’s July volume increased about 14% from the previous month. The platform supplied roughly 74.5% of the three exchanges’ combined total, extending its lead over both versions of Polymarket.
The latest data also revise the comparison with June. The Block initially reported $44.8 billion across the three venues shortly after June ended, including $31.5 billion from Kalshi. The current dashboard uses a higher June baseline of $46.95 billion, showing that historical totals were updated as more trading data became available.
Notional volume should not be treated as platform income. Traders can buy and sell the same contract several times before settlement, causing the recorded volume to rise without an equal amount of new capital entering the exchange.
Therefore, July’s record shows greater contract turnover and liquidity. It does not establish that traders deposited $50.6 billion or that the three platforms earned an equivalent amount.
Polymarket US grows while offshore activity falls
Polymarket US posted the strongest monthly growth of the three venues. Its volume increased 54% to $5 billion. In contrast, volume on Polymarket’s international platform declined 26% to $7.9 billion.
Combined volume across the two Polymarket businesses fell from about $14 billion in June to $12.9 billion in July. The U.S. platform therefore gained activity without fully offsetting the drop recorded by the international exchange.
Polymarket US opened more widely to eligible U.S. users after removing its initial app waitlist in May. The CFTC lists QCX, operating as Polymarket US, as a designated contract market. Kalshi has held the same federal designation since November 2020.
The opposing volume trends are consistent with some demand shifting toward Polymarket’s regulated U.S. exchange. However, monthly totals cannot prove that individual traders moved between the two platforms.
Rutgers University statistician Harry Crane previously estimated that about 30% of Polymarket’s offshore volume could originate from U.S. users. His wider estimated range was 19% to 48%. Crane stressed that blockchain transactions do not reveal traders’ locations, making those figures indirect estimates rather than verified customer data.
World Cup trading boosted volume before activity cooled
The FIFA World Cup, which ran from June 11 through July 19, provided a large group of frequently settling contracts. Kalshi’s market on the final between Spain and Argentina recorded approximately $1.89 billion in volume. Spain won the match 1–0.
Chainalysis separately estimated that World Cup-related blockchain prediction markets generated $20 billion from January through the tournament’s conclusion. About 400,000 wallets produced $5.7 billion during the five-week competition, while World Cup markets represented approximately 63% of prediction-market activity during that period.
Those figures are not directly comparable with the $50.6 billion monthly total. Chainalysis examined on-chain markets, while The Block’s dataset combines centralized Kalshi activity with Polymarket’s international and U.S. venues.
As crypto.news previously reported, Chainalysis also found that activity exceeded $300 million on the day of the final. Its $20 billion estimate included qualifying and pre-tournament contracts beginning in January, rather than trading conducted only during the tournament.
Open interest across Kalshi and the two Polymarket platforms fell from around $2 billion near the start of July to approximately $1.2 billion by month-end. The decline shows that many positions settled or closed as the tournament ended, even though total monthly turnover reached a record. Earlier weekly data had already shown sports activity retreating from its early-July peak.
U.S. court fights could shape August activity
The platforms reached the volume record while facing conflicting decisions over whether federal derivatives regulation blocks state gambling enforcement.
On July 31, New York sued Kalshi and accused it of running an “illegal, unlicensed gambling operation.” The state is seeking an order stopping the platform from offering unlicensed event contracts, along with fines, forfeiture and customer restitution. Those claims remain allegations and have not produced a final judgment.
Four days earlier, a Minnesota federal judge temporarily stopped the state from enforcing its prediction-market law against Kalshi and Polymarket US. The court found that the platforms were likely to succeed on part of their federal-preemption case. However, the judge warned that not every event contract necessarily qualifies as a federally regulated swap and that any permanent order could be narrower.
In related coverage, crypto.news reported that the Minnesota injunction allows both platforms to continue operating while the underlying cases proceed. The ruling did not settle whether states can regulate sports or entertainment contracts that fall outside the federal swap definition.
August data will provide the first full-month test without the World Cup. The next question is whether sports, politics and economic contracts can preserve July’s trading pace while the New York and Minnesota cases move through court.