Prediction Market Fees Comparison: 8 Platforms Ranked by What You Actually Pay
Compare prediction market fees across all 8 platforms with worked examples showing the real cost per $100 trade. Find the lowest-fee platform for your strategy.
The Fee Landscape Across 8 Platforms
Eight prediction market platforms are live in 2026. Each charges differently. Some take a cut of profits. Some charge per contract. Some bury costs in the spread. The difference between the cheapest and most expensive platform on a $100 trade can exceed $10.
This guide breaks down the exact fee math for every platform, with worked examples so you can calculate the real cost before you trade. For the full mechanics behind each fee type, read the prediction market fees explained guide.
Every Platform's Fee Structure
Here's what each platform charges, from lowest effective cost to highest.
Robinhood: $0.01-$0.02 Per Contract
Robinhood charges a flat $0.01 to $0.02 per contract. No profit-based fees. No withdrawal fees. On a 100-contract position ($100 notional), you pay $1 to $2 total.
This is the simplest fee structure in the market. You know the cost before you enter.
ForecastEx: $0.01 Per Contract
ForecastEx charges $0.01 per contract. Comparable to Robinhood's low end. The catch: you need an Interactive Brokers account, which has its own fee structure and minimum requirements. For traders already on IBKR, ForecastEx is one of the cheapest prediction market options available.
DraftKings: $0.02 Per Contract Per Side
DraftKings uses CME Group event contracts with a $0.02 fee per contract per side. That's $0.04 round trip (buy + sell or buy + settlement). On 100 contracts, you pay $4. Straightforward, but double ForecastEx and Robinhood.
FanDuel: CME Group Contracts
FanDuel partners with CME Group, making contracts available in all 50 states. The fee structure mirrors CME's standard event contract pricing. Like DraftKings, expect $0.02 per contract per side through CME infrastructure.
Polymarket: 2% on Net Profits
Polymarket charges 2% on net profits only. No fee on losing trades. No per-contract fee. If you profit $50 on a position, you pay $1. If you lose, you pay $0.
This sounds cheap, and on individual winning trades it is. But the 2% only applies to net profits across your portfolio, meaning wins offset losses before the fee kicks in. For consistently profitable traders, the effective rate stays low. For those with high turnover and mixed results, the math changes. Note: Polymarket is available globally but not to U.S. residents.
Kalshi: 7% × p × (1-p) Taker Fee
Kalshi uses a variable taker fee based on the contract price. The formula: 7% × p × (1-p), where p is the contract price. This fee peaks at $0.50 contracts (1.75 cents per contract) and drops toward zero at extreme prices.
On a $0.50 contract: fee = 7% × 0.50 × 0.50 = $0.0175 per contract. On a $0.80 contract: fee = 7% × 0.80 × 0.20 = $0.0112 per contract. On a $0.95 contract: fee = 7% × 0.95 × 0.05 = $0.0033 per contract.
The variable structure means Kalshi is expensive at 50/50 prices and competitive at extreme prices. For a deeper breakdown, see the fees explained guide.
Coinbase: Kalshi Front-End
Coinbase operates as a front-end for Kalshi contracts. Same contracts, same fee structure. The difference is the interface and the Coinbase account integration. Fee math is identical to Kalshi.
PredictIt: 10% Profits + 5% Withdrawal
PredictIt is the most expensive platform by a wide margin. It charges 10% on profits per market plus a 5% withdrawal fee on all funds removed from the platform. These fees stack.
If you profit $100 across your PredictIt portfolio, you pay $10 in profit fees. When you withdraw that $90, PredictIt takes another $4.50. Your $100 profit becomes $85.50. That's a 14.5% effective rate before accounting for opportunity cost.
Worked Example 1: 100 Contracts at $0.60
You buy 100 contracts at $0.60 ($60 total investment). The contract resolves Yes, paying $1.00 per contract. Your gross profit: $40.
| Platform | Fee Calculation | Fee Paid | Net Profit | Effective Rate |
|---|---|---|---|---|
| Robinhood | 100 × $0.02 | $2.00 | $38.00 | 5.0% |
| ForecastEx | 100 × $0.01 | $1.00 | $39.00 | 2.5% |
| DraftKings | 100 × $0.04 | $4.00 | $36.00 | 10.0% |
| FanDuel | 100 × $0.04 | $4.00 | $36.00 | 10.0% |
| Polymarket | $40 × 2% | $0.80 | $39.20 | 2.0% |
| Kalshi | 100 × $0.0168 | $1.68 | $38.32 | 4.2% |
| Coinbase | 100 × $0.0168 | $1.68 | $38.32 | 4.2% |
| PredictIt | $40 × 10% | $4.00 | $36.00 | 10.0% |
Polymarket wins this scenario. ForecastEx is the cheapest U.S.-regulated option. PredictIt and DraftKings tie for most expensive, and PredictIt gets worse when you withdraw.
Run your own numbers with the fee calculator.
Worked Example 2: High-Probability Contract at $0.90
You buy 100 contracts at $0.90 ($90 total investment). The contract resolves Yes. Gross profit: $10.
| Platform | Fee Calculation | Fee Paid | Net Profit | Effective Rate |
|---|---|---|---|---|
| Robinhood | 100 × $0.02 | $2.00 | $8.00 | 20.0% |
| ForecastEx | 100 × $0.01 | $1.00 | $9.00 | 10.0% |
| DraftKings | 100 × $0.04 | $4.00 | $6.00 | 40.0% |
| FanDuel | 100 × $0.04 | $4.00 | $6.00 | 40.0% |
| Polymarket | $10 × 2% | $0.20 | $9.80 | 2.0% |
| Kalshi | 100 × $0.0063 | $0.63 | $9.37 | 6.3% |
| Coinbase | 100 × $0.0063 | $0.63 | $9.37 | 6.3% |
| PredictIt | $10 × 10% | $1.00 | $9.00 | 10.0% |
High-probability contracts change the rankings. Kalshi's variable fee drops sharply at extreme prices, making it competitive. But flat per-contract fees from DraftKings and Robinhood become brutal when profits are thin. DraftKings takes 40% of a $10 profit on 100 contracts.
This is why fee structure matters more than fee level. A platform that's cheap at $0.50 can be expensive at $0.90.
Which Platform Has the Lowest Fees?
The answer depends on three variables: contract price, position size, and whether you win.
For contracts near $0.50: Polymarket (2% on profits) and ForecastEx ($0.01/contract) are cheapest. Kalshi is most expensive among regulated U.S. platforms at this price point because its fee formula peaks here.
For contracts near $0.90 or $0.10: Kalshi becomes competitive because 7% × 0.90 × 0.10 = $0.0063 per contract. Per-contract fee platforms like DraftKings stay at $0.04 regardless of price.
For frequent traders with mixed win rates: Polymarket's profit-only fee structure rewards consistency. You never pay fees on losses. Flat per-contract fees hit every trade regardless of outcome.
For large positions: Per-contract fees scale linearly. Polymarket's percentage-based fee stays proportional. On a 1,000-contract position, DraftKings charges $40. Polymarket charges 2% of whatever you profit.
Use the EV calculator to model how fees affect expected value at different price points and win rates.
The Hidden Costs Beyond Listed Fees
Published fee schedules don't capture the full cost of trading.
Spread costs. Illiquid markets have wide bid-ask spreads. Paying $0.62 for a contract worth $0.60 costs more than any platform fee. Use the liquidity calculator to estimate slippage before entering.
Withdrawal fees. PredictIt's 5% withdrawal fee is unique and devastating for active traders who move money in and out. No other major platform charges for withdrawals in 2026.
Opportunity cost. ForecastEx requires an Interactive Brokers account. DraftKings and FanDuel route through CME Group. These structures may tie up capital differently than standalone platforms.
Gas fees. Polymarket settles on Polygon using USDC. Transaction costs are minimal but nonzero, especially during network congestion.
For a complete platform-by-platform breakdown beyond fees, read the best prediction market 2026 comparison.
Fee Impact on Strategy
Fees don't just reduce profits. They reshape which strategies work.
Arbitrage. Cross-platform price differences of 2-3 cents look profitable until fees eat both sides. A $0.03 arb on DraftKings ($0.04 round-trip fee) is negative EV before you start. Run potential arbs through the arbitrage calculator to check profitability after fees. Read the cross-platform arbitrage guide for the full framework.
High-frequency trading. Per-contract fees punish frequent traders. Polymarket's profit-only model is structurally better for high-turnover strategies. Kalshi's variable fee sits in between.
Position sizing. Fees change your optimal Kelly fraction. A 5% edge with 2% fees is a different bet than a 5% edge with zero fees. The break-even calculator shows the minimum edge needed to overcome fees on any platform. See the position sizing guide for the full framework.
Cross-platform edge. Different fee structures across platforms create situations where the same contract is cheaper to trade on one exchange vs. another. This is a real, exploitable edge. Read the cross-platform edge guide for how to systematically find these opportunities.
The Bottom Line
There is no single cheapest platform. Polymarket has the lowest fees for profitable traders with its 2% profit-only model, but it's not available in the U.S. For U.S. traders, ForecastEx and Robinhood offer the lowest flat rates. Kalshi is cheapest on extreme-probability contracts. PredictIt is the most expensive option in every scenario.
The right platform depends on your strategy, your typical contract prices, and your win rate. Stop comparing headline fee numbers. Calculate the actual cost on your specific trades.
The fee calculator does this math in seconds. Enter your contract price, position size, and platform. Get the real number. Trade accordingly.