Prediction Market Fee Calculator

Trading fees eat into your returns on every prediction market trade. The problem is that each platform calculates fees differently — Kalshi uses a probability-weighted formula, Polymarket charges a flat percentage of position value, and FanDuel Predicts takes a cut of your potential payout. This calculator shows you the exact cost on all three platforms side by side, so you can see which one is cheapest for the trade you’re planning.

Last updated: March 2026

Prediction Market Fee Calculator


$0.

$0.01$0.50$0.99

Order Type


Taker = you accept an existing price. Maker = you set your own price and wait for a fill.

Adjust the inputs above to compare fees across platforms.

Fees calculated using each platform’s published fee schedule as of March 2026. Kalshi S&P 500 and Nasdaq-100 event contracts use a reduced taker multiplier (0.035) not reflected here. Deposit fees (e.g., Kalshi’s 2% debit card surcharge) are not included. See our methodology for how we verify fee data.


How Fees Work on Each Platform

Every prediction market charges trading fees, but the structures vary significantly. Understanding the differences matters because the cheapest platform for a 50-cent contract is not necessarily the cheapest for a 10-cent or 90-cent contract.

Kalshi Fees

Kalshi uses a probability-weighted fee formula that scales with the uncertainty of the contract. The taker fee per contract is:

Fee = ceil(0.07 × Price × (1 − Price) × 100) / 100

In practice, this means:

  • Fees peak at $0.50 contracts — about $0.02 per contract — because 0.50 × 0.50 = 0.25, the maximum value of the Price × (1 − Price) term
  • Fees decrease toward the extremes — a $0.10 contract costs about $0.01 in fees; a $0.90 contract also costs about $0.01
  • Maker orders use a 75% lower multiplier — 0.0175 instead of 0.07, so placing limit orders is substantially cheaper
  • S&P 500 and Nasdaq-100 event contracts use a halved taker multiplier of 0.035, making equity-index trading cheaper
  • Deposit surcharge: 2% on debit card, Apple Pay, and Google Pay deposits. Bank transfers (ACH) are free. This is a deposit fee, not a trading fee, but it affects your effective cost.

All fees are rounded up to the nearest cent per contract. For a deeper look at Kalshi’s platform, see our Kalshi Review.

Polymarket Fees

Polymarket’s US platform uses a simple flat-rate taker fee of 0.10% — one-tenth of one percent of the position value (contracts × price). There are zero maker fees.

  • The math is straightforward: buy 100 contracts at $0.50 and you pay $0.05 in fees (100 × $0.50 × 0.001)
  • No deposit fees on the platform itself, though third-party crypto on-ramp services (used for the global platform) may charge separately
  • Global platform: near-zero fees on most markets, though the global platform is not available to US traders
  • At this rate, Polymarket is typically the cheapest platform for taker orders, particularly on contracts near $0.50 where Kalshi’s probability-weighted formula peaks

For the full breakdown, see our Polymarket Review.

FanDuel Predicts Fees

FanDuel Predicts charges a flat 2% fee on the potential profit of every trade. Potential profit per contract is $1.00 minus the contract price — the amount you would receive above your cost if you win.

  • No maker/taker distinction — every order pays the same 2% rate
  • Fee scales with potential upside: buying cheap contracts (high potential profit) costs more in fees than buying expensive contracts
  • Example: 10 contracts at $0.30 = potential profit of $7.00, so the fee is $0.14
  • Zero deposit fees on all methods, including PayPal, Venmo, and debit cards
  • This makes FanDuel the most expensive platform for cheap contracts (where the potential payout is large) but relatively competitive on high-priced contracts

See our FanDuel Predicts Review for the full platform analysis.

When Fees Matter Most

On a single small trade, the difference between platforms might be a few cents. But fees compound quickly in two scenarios:

  • High volume: If you trade frequently — say, 50+ contracts per week — the platform with the lowest fee structure can save you hundreds of dollars per year. At that volume, maker orders on Kalshi or taker orders on Polymarket pull significantly ahead of FanDuel’s flat 2%.
  • Low-probability contracts: On contracts priced below $0.10, FanDuel’s 2% of potential payout is disproportionately expensive because the potential profit per contract is large. Kalshi’s fees actually decrease in this range because the probability-weighted formula produces lower values near the extremes.

For most casual traders making a few trades per month, the fee difference between platforms is real but secondary to factors like market selection, regulation, and deposit methods. Our Best Prediction Market Platforms ranking weighs fees alongside eight other categories.

Common Questions

Which prediction market has the lowest fees?

For taker orders on most contract prices, Polymarket’s US platform is cheapest at 0.10% of position value. For maker (limit) orders, Polymarket has zero fees and Kalshi charges a reduced rate. FanDuel Predicts is generally the most expensive due to its 2% of potential payout structure, though the gap narrows on high-priced contracts near $0.90 or above.

How are Kalshi fees calculated?

Kalshi uses a probability-weighted formula: the taker fee per contract equals ceil(0.07 × Price × (1 − Price) × 100) / 100, rounded up to the nearest cent. The fee peaks at $0.02 per contract on 50-cent contracts and decreases as the price moves toward $0.01 or $0.99. Maker orders use the same formula with a lower multiplier of 0.0175.

Does Polymarket charge fees?

Yes. The US platform charges a 0.10% taker fee (one-tenth of one percent of position value). There are zero maker fees. The global platform has near-zero fees on most markets. There are no deposit fees from Polymarket itself, though crypto on-ramp services may charge separately.

What does FanDuel Predicts charge per trade?

FanDuel Predicts charges 2% of potential profit on every trade. Potential profit = contracts × ($1.00 − contract price). There is no maker/taker distinction — all orders pay the same rate. There are zero deposit fees on all payment methods.

Do prediction markets charge deposit fees?

It depends on the platform and payment method. Kalshi charges a 2% surcharge on debit card, Apple Pay, and Google Pay deposits, but bank transfers (ACH) are free. Polymarket and FanDuel Predicts charge zero deposit fees on all methods (though third-party crypto on-ramps used with Polymarket’s global platform may have their own costs).

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