Polymarket US Fees Explained: The Formula, With Worked Examples
Codes mentioned here live on the Polymarket US page, with current verification dates.
Most exchanges quote a trading fee as one flat percentage. Polymarket US doesn’t. Its taker fee is a formula that depends on the price of the contract you’re trading, which means the same trade can cost a very different share of your money depending on whether you’re backing a long shot or a near-certainty. Here’s how the formula actually works, with the numbers run out, straight from Polymarket’s own fee schedule.
The formula
Polymarket US prices every contract between 1¢ and 99¢, where the price is roughly the market’s estimate of the probability the outcome happens. A contract pays $1 if it’s right and $0 if it’s wrong. The standard taker fee on that trade is:
Fee = 0.0695 × C × p × (1 − p)
- C is the number of contracts you’re trading.
- p is the price per contract, as a decimal (50¢ is 0.50).
- 0.0695 is the fee coefficient Polymarket sets for standard markets.
The fee is deducted from your balance the moment the trade fills. There’s no separate line item to hunt for — it comes straight out at execution.
Why the dollar fee peaks at 50¢
The term doing the work in that formula is p × (1 − p). Multiply any price between 0 and 1 by its complement, and the result is largest exactly at the midpoint — 0.50 × 0.50 = 0.25, which is bigger than 0.10 × 0.90 = 0.09 or 0.90 × 0.10 = 0.09. That’s not a coincidence of Polymarket’s design; it’s just what that kind of product looks like on a graph; it rises from zero at the edges to a single peak in the middle.
Run the same 100-contract trade at three prices and the fee traces that curve exactly:
| Contract price | Contracts | Fee (dollars) | Cost to open the position | Fee as % of cost |
|---|---|---|---|---|
| 10¢ | 100 | $0.63 | $10.00 | 6.3% |
| 50¢ | 100 | $1.74 | $50.00 | 3.5% |
| 90¢ | 100 | $0.63 | $90.00 | 0.7% |
A toss-up contract at 50¢ carries the highest fee in raw dollars — $1.74 on a 100-lot, which Polymarket’s own documentation lists as the maximum possible fee on that trade size. A long-shot bet at 10¢ and a near-lock at 90¢ both land at $0.63, because the formula is symmetric around the midpoint: p(1 − p) gives the same answer for p and for 1 − p.
But look at the last column. As a percentage of the money you’re actually putting at risk, the pattern flips. The 10¢ long shot pays 6.3% of its cost in fees; the 90¢ favorite pays well under 1%. That’s because the fee grows with p(1 − p) while the cost of the position grows with p alone, and the fee-to-cost ratio works out to 0.0695 × (1 − p) — a number that falls steadily as the price rises. In plain terms: cheap, low-probability contracts cost more in fees relative to what you’ve staked than expensive, high-probability ones, even though the highest single fee in dollar terms sits at the middle of the price range.
Maker rebates exist, but almost no retail trader qualifies for one
Polymarket US splits every fill into two sides. A taker order crosses the book and fills immediately — that’s the side that pays the formula above. A maker order sits on the book waiting to be filled, and instead of paying a fee, a maker can earn a rebate.
The catch is tiering. Polymarket sets maker rebate tiers by a trader’s maker volume over the prior calendar month, and the bottom tier — under $10 million in monthly maker volume — gets no rebate at all. A rebate only starts at the second tier, $10 million to just under $50 million in monthly maker volume, and even there it’s modest: a coefficient of -0.0035, worth roughly 5% of what the equivalent taker fee would have been. The richest rebate, reserved for traders clearing $200 million or more a month, is still only around 15% of the taker fee. For scale, that $10 million monthly floor is a trading desk’s threshold, not an individual bettor’s. Placing a limit order instead of a market order doesn’t cost anything extra, but it also won’t earn an occasional retail trader a rebate — it just avoids paying the taker fee’s debit on that particular fill if the order never gets matched.
The schedule isn’t fixed, and Polymarket says so
The numbers above reflect the fee schedule Polymarket US put into effect at 1:00 PM ET on October 19, 2026, per its own documentation. That’s worth flagging for two reasons. First, a fee schedule that updates is, by definition, a fee schedule that can update again — treat the coefficient and the tiers here as a snapshot, not a permanent constant, and check Polymarket’s live fee page before you size a trade around the exact math. Second, Polymarket’s own page describes special, temporary tiering rules that apply only through the end of October 2026 before standard monthly tiering takes over — a reminder that even the mechanism for assigning tiers is still being adjusted, not just the coefficients inside it.
This is the same caution that applies to any exchange’s published rate card: useful as a reference the day you read it, not a number worth memorizing as if it were permanent. The primer on how exchange fees generally work — maker/taker splits, spreads, withdrawal costs — covers the same idea for order-book exchanges more broadly; Polymarket’s price-dependent formula is a variation on that same maker/taker split, just with the taker side priced by a curve instead of a flat percentage.
What this means for the $25 referral credit
If you’re trading with Polymarket US’s referral credit rather than your own cash, the fee comes out of that credit the same way it would with real money — there’s no fee waiver tied to using a promotional balance. Our breakdown of the $25 Polymarket US referral credit runs the fee into its worked examples at those same three price points, which is where this formula actually shows up in practice: a credit spent on a long-shot contract gives up a slightly larger share of itself to fees than the same credit spent on a favorite.
The bottom line
Polymarket US doesn’t charge one number — it charges a curve. Takers pay 0.0695 × contracts × price × (1 − price), which peaks in dollar terms at the 50¢ midpoint but actually takes the biggest percentage bite out of cheap, low-probability contracts. Makers can earn a rebate instead of paying the fee, but only once their monthly volume clears a threshold far above what an individual trader typically reaches. And because Polymarket has already shown it will revise both the coefficients and the tiering rules, the fee page itself — not a number copied from an article — is the one to check before a trade.
Our Polymarket US hub has the current referral code and the date we last checked it against Polymarket’s documentation, under the same verification standard explained on how we verify.