Prediction Market Fees Comparison: 8 Platforms Ranked by What You Actually Pay

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: Per-Category Taker Fees

Polymarket charges per-category taker fees. The old 2% profit fee is gone. Fees are charged per trade using the same curve shape as Kalshi: fee = C × feeRate × p × (1-p), where C is the number of shares.

Taker rates by category: politics, finance, tech, and mentions 0.04; sports, economics, culture, weather, and other 0.05; crypto 0.07; geopolitics 0. Geopolitical and world-events markets are fee-free. Makers (limit orders) pay zero and earn a rebate. Settlement is free, since the formula returns zero at $1.00 and $0.00.

At the peak (50¢ contracts), politics costs $0.0100/contract. Sports costs $0.0125/contract. Crypto costs $0.0175/contract, matching Kalshi. Fees drop sharply at extreme prices. For the full breakdown, see Polymarket fees explained.

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.

Polymarket Politics takers land just under ForecastEx here, and Polymarket makers pay zero. The exact fee depends on the market category — Crypto would be higher, geopolitics free. ForecastEx is the cheapest U.S.-regulated taker 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.

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 makers pay zero, which beats everyone. Among taker fees, ForecastEx ($0.01/contract) and Polymarket politics ($0.0100/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. Polymarket runs the same p × (1-p) curve, so its fees drop sharply at the extremes too.

For frequent traders: Polymarket's taker fee applies on every trade that crosses the book, similar to Kalshi, but makers pay zero. On rate alone, sports (0.05) is about 29% cheaper than Kalshi and politics (0.04) about 43% cheaper; crypto (0.07) matches Kalshi.

For large positions: Fees scale linearly. On a 1,000-contract Politics position at 50¢, Polymarket takers pay $10.00. Kalshi taker charges $17.50. DraftKings charges $40.00. Polymarket makers pay $0.

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. Flat per-contract fees punish frequent traders. Polymarket makers pay zero, which is structurally better for high-turnover strategies that rest limit orders on the book. 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's per-category taker fees range from zero (geopolitics, and every maker order) up to crypto at 0.07, which matches Kalshi. On politics and sports, Polymarket takers undercut Kalshi at every price, and Polymarket makers pay nothing at all. For U.S. traders who want flat, predictable rates, ForecastEx and Robinhood are lowest. 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.