Kalshi's June Volume Hit $9.4B — Its Best Month Ever — With Daily Trading Topping $1B During the World Cup
Kalshi recorded $9.4 billion in trading volume in June 2026, up from $5.3 billion in May and the platform's highest monthly total ever. Total notional volume exceeded $31 billion, and daily activity consistently topped $1 billion during the World Cup. Canada vs. Morocco alone drew $48 million on Kalshi and $26.8 million on Polymarket, the largest single-match figure yet.
Kalshi recorded $9.4 billion in trading volume in June 2026, up from $5.3 billion in May and the highest monthly total in the platform's history. Total notional volume — the face value of all contracts traded, reflecting turnover rather than new capital deployed — exceeded $31 billion, and daily activity consistently surpassed $1 billion at the peak of World Cup activity. The numbers represent the clearest evidence yet that the 2026 FIFA World Cup has functioned as a mainstream consumer breakthrough for US prediction markets, not just a volume spike that returns to baseline when the tournament ends.
The knockout rounds drove the biggest individual-match numbers. Canada vs. Morocco, played in the Round of 16, drew over $48 million in trading volume on Kalshi and $26.8 million on Polymarket — the largest single-match figure the platforms have yet disclosed. US advancement markets generated millions in additional trades as the host nation progressed. The pattern follows a familiar bracket-compression dynamic: as the field narrows, each remaining match carries more outcome weight, more traders take positions, and existing holders add to them. The Round of 16 is where the casual World Cup bettor — the user who opened an account for the group stage and won a few contracts — turns into an active trader holding positions into the quarterfinals.
Kalshi also announced a partnership with ADI Predictstreet ahead of and during the tournament, strengthening the platform's data and market infrastructure for World Cup contracts. Polymarket reached approximately $4.3 billion in monthly volume in June, bringing the combined total across major US prediction platforms to an estimated $44.8 billion for the month — a figure that includes volume on both regulated US exchanges and Polymarket's international platform. To put the scale in context: $44.8 billion in monthly volume approaches the territory of mid-sized US commodities futures exchanges, from a sector that did not meaningfully exist at the retail level in the United States before 2024.
One distinction worth holding onto as these numbers circulate: trading volume and notional volume measure different things. Kalshi's $9.4 billion in trading volume reflects the sum of all contract transactions at their traded prices. The $31 billion notional figure reflects the total face value of all contracts, which is a higher number because event contracts typically settle at $1 and are traded at fractional prices reflecting probability. Both are real measures; neither is inflated, but they should not be compared directly against each other or against figures from traditional betting handles, which are calculated differently. The sector is still developing common disclosure standards. What the June data does confirm unambiguously: the volume trajectory that began when the World Cup opened on June 11 did not plateau — the knockout rounds accelerated it.
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Recent updates
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