Most Polymarket and Kalshi Users Lose Money Amid Volume Surge
Combined monthly trading hit $29.8 billion, while a review of platform data found more than 70% of Polymarket users lost money and Kalshi losers outnumber winners about 2.9-to-1.
Combined monthly notional trading on Polymarket and Kalshi reached $29.8 billion last month, a roughly 588% increase from a year earlier. A review of platform data shows most users lost money and profits were concentrated in a very small share of accounts.
Polymarket lists at least 2.3 million total accounts. A review of 1.6 million accounts active since November 2022 found more than 70% of users incurred losses. The review showed 0.1% of accounts captured 67% of total profits; fewer than 2,000 accounts together netted nearly $500 million.
Typical retail accounts registered modest losses between $1 and $100. The bottom 10% of accounts lost an average of about $4,000 each. An academic analysis covering November 11, 2022, through March 29, 2026, found 68.8% of users had lost money and that 1% of traders accounted for 76.5% of total profits.
Separate platform data indicate more than 100,000 accounts lost at least $1,000 since January 2025, roughly double the number of accounts with comparable gains.
On Kalshi, a company spokeswoman reported that losing users outnumber winners by about 2.9 to 1 based on recent monthly data. A review of more than 35,000 completed “mention” markets on Kalshi found contracts priced at 50% paid out only around 40% of the time. Researchers estimated that traders who buy a “yes” contract at the first price they see-a common pattern for casual users-lose about 11% of the money they stake on average, a level of loss compared with the house edge on many slot machines in a university study.
The reviews describe a pattern in which a small number of sophisticated traders and trading firms, often using extensive data feeds and automated strategies, generate the bulk of returns while many casual traders record losses. The findings come as user numbers and market size increased liquidity and expanded market offerings.
Prediction markets offer binary contracts that pay $1 if a specified event occurs and $0 if it does not; prices reflect the market’s implied probability of the outcome. Platform operators were asked for comment on the findings.
