Trading fees eat into your returns on every prediction market trade — and the platforms make comparison genuinely hard by charging in incompatible ways: probability-weighted formulas (Kalshi, Polymarket US, OG, Novig, ADI Predictstreet), per-contract fees (Underdog, Fanatics), a percentage of payout (FanDuel), and a percentage of winnings charged only when you profit (ProphetX). This calculator shows the cost on all nine platforms we review, side by side, for the trade you’re planning.
Fee schedules as of Oct 2, 2026. Updated for Polymarket US’s new 0.0695 taker rate (effective October 1, 2026), OG’s US fee formula, Fanatics Markets’ September 2 table (capped at 2¢), Underdog’s commission plus an exchange fee we could not verify, ProphetX’s separate parlay schedule, and Novig’s regulated exchange. Added Novig and ADI Predictstreet. The same fee data powers our study The True Cost to Trade on Prediction Markets, which adds live bid-ask spreads.
Prediction Market Fee Calculator
Taker = you accept an existing price. Maker = you set your own price and wait for a fill. Maker/taker pricing differs on Kalshi, Polymarket US, OG and Novig; the other platforms charge the same fee either way.
Fees calculated from each platform’s published fee schedule as of Oct 2, 2026, for buying contracts and holding them to settlement (selling early is charged again on most platforms). Where the fee depends on the market type (OG, Novig) or on an exchange fee we could not verify (Underdog Predict), the card shows a low–high range; ProphetX shows $0 if the trade loses up to its fee if it wins. The “lowest fixed fee” badge only compares platforms with a single fee for the trade. Kalshi series with a non-standard fee multiplier are not reflected. ADI Predictstreet’s rate is read from its public API. Deposit surcharges are not included. Full sources: The True Cost to Trade. See our methodology for how we verify fee data.
How Fees Work on Each Platform
Every prediction market charges trading fees, but the structures differ enough that the cheapest platform changes with the contract price, your order type, and whether you win. Here’s each platform’s published schedule as of Oct 2, 2026.
Kalshi
Probability-weighted formula, confirmed in Kalshi’s July 7, 2026 fee schedule: taker fee per contract = 0.07 × Price × (1 − Price), rounded up to the nearest cent. Fees peak around 1.75¢ per contract at 50¢ and shrink toward both extremes. Resting (maker) orders are free on most markets; series with maker fees charge 0.0175 × Price × (1 − Price), and some series use a different multiplier. Deposits: ACH free; 2% surcharge on debit/Apple/Google Pay. Full details in our Kalshi review.
Polymarket (US platform)
Same formula shape as Kalshi: since October 1, 2026, taker fee = 0.0695 × Contracts × Price × (1 − Price), rounded to the cent (about $1.74 per 100 contracts at 50¢). Makers earn a rebate of 0.0125 × C × P × (1 − P). High-volume takers can get 10–50% rebates; combos use a higher curve. No deposit or withdrawal fees. iOS-only for US users as of July 2026. Full details in our Polymarket review.
OG
For US customers on most markets, OG uses a formula: taker 0.07 × C × P × (1 − P), maker 0.0175 × C × P × (1 − P). Crypto, FX, commodities and index markets cost a flat $0.02 per contract. Fees apply when you open and again if you close early; the settlement fee is waived. Deposits: bank transfers free; 1.49% on debit cards, 1.99% on PayPal. Full details in our OG review.
ProphetX
The outlier: 2% of net winnings per market, charged only when you profit. Lose the trade, pay nothing. That applies to straight trades; parlays follow ProphetX’s separate parlay fee schedule (version 1.2, October 1, 2026). No deposit or withdrawal fees on any method. Because losing trades are free, the real cost depends on your win rate. Full details in our ProphetX review.
FanDuel Predicts
A flat 2% of potential payout — and since every contract pays $1.00 if it wins, that works out to 2¢ per contract regardless of price (a $95 potential payout costs $1.90). No maker/taker distinction; the fee also applies when you cash out early. Zero deposit fees on every method including PayPal and Venmo. Full details in our FanDuel Predicts review.
Underdog Predict
A broker commission of $0.01 per contract on each side (opening or closing), per Underdog’s UDM fee schedule. Exchange fees are passed through on top; the exchange fee is reported at 0.07 × C × P × (1 − P), but we could not open the exchange’s own fee schedule, so the upper end of the calculator’s range is unverified. No deposit or redemption fees. One quirk worth knowing: a $4/month inactivity fee applies after 18 months of no account activity. Full details in our Underdog Predict review.
Fanatics Markets
A price-dependent per-contract table (official schedule effective September 2, 2026), capped at 2¢ per contract for prices between 20¢ and 80¢ and tapering toward the extremes (0.34¢ at 1¢, 1.6¢ at 10¢ and 90¢, 0.64¢ at 99¢). Charged per execution — on buys and on sells — with order totals rounded up to the next cent and a 1¢ minimum. ACH deposits free; up to 2% on debit/Apple Pay; withdrawals free. Full details in our Fanatics Markets review.
Novig and ADI Predictstreet
Novig relaunched in August 2026 as a CFTC-regulated exchange, replacing its sweepstakes product. Makers pay nothing; takers pay nothing on pre-game straight trades, 0.03 × P × (1 − P) on most live trades and 0.06 × P × (1 − P) on futures (the calculator shows $0 up to the futures rate). ADI Predictstreet charges k × P × (1 − P) per contract to makers and takers alike; its public API currently reports k = 600 basis points (0.06). See our Novig review and ADI Predictstreet profile.
When Fees Matter Most
- High-probability contracts: This is where the structures diverge hardest. At 90¢, Kalshi and Polymarket US charge about 0.63¢ per contract, while FanDuel still charges 2¢ and Fanatics 1.6¢. OG ranges from 0.63¢ (most markets) to 2¢ (crypto, FX, commodities, indices). Formula platforms win big at the extremes.
- High volume: If you trade 50+ contracts a week, the platform gap compounds to hundreds of dollars a year. Maker orders on Polymarket US earn a rebate; resting orders on most Kalshi markets are free.
- If you win more than you lose: ProphetX’s winnings-only fee means your losing trades subsidize nothing. Profitable sports traders should run their actual win rate against the entry-fee platforms.
For most casual traders, fees are secondary to market selection, regulation, and funding options. Our platform rankings weigh fees alongside eight other categories.
Common Questions
Which prediction market has the lowest fees?
It depends on the price and market. At 50¢, 100 contracts cost $1.75 on Kalshi, $1.74 on Polymarket US, $1.50 on ADI Predictstreet and $2.00 on Fanatics Markets and FanDuel Predicts; Novig’s pre-game trades are free, and ProphetX charges only on winnings. Toward 1¢ and 99¢, the formula platforms get much cheaper than FanDuel’s flat 2¢.
How are Kalshi fees calculated?
Taker fee per contract = 0.07 × Price × (1 − Price), rounded up to the nearest cent — about 1.75¢ at 50¢, under a penny beyond 85¢ or below 15¢. Resting orders are free on most markets. Confirmed against Kalshi’s July 7, 2026 fee schedule.
Does Polymarket charge fees?
Since October 1, 2026, the US platform charges takers 0.0695 × Price × (1 − Price) per contract (about $1.74 per 100 contracts at 50¢) and pays makers a rebate of 0.0125 × Price × (1 − Price). Deposits and withdrawals are free.
What does FanDuel Predicts charge per trade?
2% of potential payout — effectively 2¢ per contract at any price, on every order type, including early cash-outs. Deposits are free on all methods.
How do ProphetX fees work?
2% of net winnings per market, charged only when you profit. Losing trades pay nothing. Parlays follow a separate parlay fee schedule. No deposit or withdrawal fees.
Do prediction markets charge deposit fees?
Bank transfers are free everywhere. Card-based deposits often aren’t: Kalshi adds 2% on debit/Apple/Google Pay, OG charges 1.49% on debit and 1.99% on PayPal, and Fanatics up to 2% on debit/Apple Pay. FanDuel Predicts and ProphetX charge no deposit fees at all (ProphetX doesn’t accept cards).
Related Pages
- Best Prediction Market Platforms — all nine platforms ranked across 9 categories
- Legality Checker — what’s tradable in your state
- Your First Prediction Market Trade — step-by-step walkthrough
- Our Methodology — how we verify fee data
About the author. Arthur Angelo writes about prediction
markets at PredictionScout, comparing prices, fees, rules, and liquidity across platforms with a focus on
transparency and practical data. Fees are checked against published schedules and regulatory claims against
CFTC filings; where a fact can’t be verified, the page says so. See our
scoring methodology and
editorial policy.