How profits are split
Akey and co-authors examined a large Polymarket trading sample and found that gains among profitable accounts were highly concentrated. Their 76.5% figure uses the top 1% of users who had positive profit and loss—not the top 1% of everybody with an account. It is a result from a particular platform and period, not an expected return for future participants.
Makers, takers and the cost of immediacy
A maker posts an order that can be matched later; a taker accepts an available order. Burgi, Deng and Whelan report that takers in their Kalshi analysis lost almost 32% on average, while makers lost about 10%. Selection, fees and trading against better-informed participants all matter. A maker can still lose, and providing liquidity is not a risk-free income stream.
Why cheap contracts can be expensive
A ten-cent contract may look affordable, but it is only fairly priced if the event occurs often enough after costs. Longshots can attract buyers for the excitement of a large payout. If the implied chance is higher than the true chance, repeatedly buying them may lose money despite occasional wins. This is a behavioural and pricing risk, not a formula for finding easy profit.
What a UK reader can—and cannot—infer
These figures come from US or globally accessible services. Different operators have different contracts, customer protections, markets and entry rules. Before comparing them with a UK exchange, check the legal operator and product. The safest conclusion is about uncertainty and concentrated outcomes, not a recommended trading tactic.
Average loss in the Kalshi sample
| Measure | % average loss |
|---|---|
| Takers | −32% |
| Makers | −10% |
Reading note. Bars encode the magnitude of loss; a taller bar means a worse average result. These are sample averages, not forecast returns.
Methodology.
The headline is from an academic working paper, and the maker/taker comparison is from a separate Kalshi analysis. Samples, periods and profit measures differ. This page does not pool them into a single population. The cited papers disclose their own authorship and funding; no operator paid this site for placement.
Sources.
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01
Who Wins and Who Loses in Prediction Markets? Evidence from Polymarket (opens in a new tab)
Research papersFunder: Academic working paper; check the paper for author disclosures.
Akey and co-authors analyse Polymarket trading gains across $67bn in volume. Working-paper estimates may be revised.
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02
The economics of Kalshi prediction markets (opens in a new tab)
Research papersFunder: CEPR/VoxEU publication; see authors’ disclosures.
Burgi, Deng and Whelan report average losses for maker and taker groups, not guaranteed outcomes for individuals.
Follow the original documents for definitions, scope and subsequent revisions. Browse the full source library ↗