Polymarket fees: what a quoted price actually costs

Polymarket is not universally fee-free. As of October 11, 2026, its international platform charges taker fees across most market categories, while makers pay no trading fee. Geopolitical and world-events markets remain fee-free. Polymarket US has a separate schedule, so the platform matters before the calculation does. These distinctions appear in the official international fee documentation and US fee schedule.

For a reader interpreting market odds, the key distinction is between the quoted share price and the fee-inclusive cost. A 50-cent price can still be read as a 50% implied probability, but buying at that price may require a higher probability to break even.

International Polymarket: the fee formula

The current formula is:

Fee = shares × fee rate × price × (1 − price)

Use the execution price in decimal dollars: 50 cents means 0.50, not 50. The result is the dollar-denominated fee. The fee rate is a coefficient in this formula, not a flat percentage of the money spent.

Market category	Fee coefficient	Fee for 100 shares at $0.50	Fee as % of the $50 purchase
Crypto	0.07	$1.75	3.5%
Sports, economics, culture, weather, other/general	0.05	$1.25	2.5%
Finance, politics, mentions, tech	0.04	$1.00	2.0%
Geopolitics/world events	0	$0	0%

The coefficients and fee amounts come from Polymarket’s published schedule; the percentages are calculated by dividing the fee by the purchase value. In particular, politics is not automatically fee-free just because geopolitical markets are.

For a fixed number of shares, the dollar fee peaks at 50 cents and falls symmetrically toward either extreme. But its percentage of a buyer’s outlay is not symmetric. Under the crypto coefficient, 100 shares at 10 cents cost $10 plus a $0.63 fee; at 90 cents they cost $90 plus the same $0.63 fee. That is 6.3% versus 0.7% of the purchase value.

The international schedule rounds fees to five decimal places, with a smallest charged fee of 0.00001 USDC. For a specific contract, check its feesEnabled and feeSchedule fields rather than relying only on its topic label. Polymarket documents those fields in Market Details.

Maker versus taker is about the fill

A maker adds a resting order to the order book; a taker executes against available liquidity. A limit order is not necessarily a maker order: it can match immediately. A post-only order, by contrast, is rejected if it would immediately take liquidity. These mechanics are described in Polymarket’s order documentation.

International makers pay no trading fee and can earn rebates on qualifying executed liquidity. Those rebates are calculated daily and depend on the fee value generated by their fills—not simply on placing an order. Takers can also receive tier-based rebates tied to their trailing-30-day weighted volume. Both programs require at least $1 in accrued rebates before issuing a payout. Treat rebates as separate credits rather than assuming every trader receives the same discount. See the official maker and taker rebate rules.

Polymarket US uses different rates and rounding

The current US schedule took effect October 7, 2026, at 10 a.m. ET. For standard contracts, it uses the same shares × coefficient × price × (1 − price) structure, but with a 0.0695 taker coefficient. A single fill of 100 contracts at 50 cents incurs a $1.74 fee after rounding. Table Tennis uses 0.10, producing a $2.50 fee for that fill.

Standard maker fills receive a rebate calculated with a 0.0125 coefficient. US fees and rebates use nearest-cent, half-to-even rounding, with an additional cumulative cap on taker rounding across an order’s fills. Combos have a separate taker formula and no maker rebate. US taker rebate tiers also differ from the international program: they use prior-calendar-month taker volume and pay weekly. All of these rules are in the US fee schedule.

What fees do to break-even probability

Suppose you buy 100 international crypto YES shares at $0.50, all as a taker, with no rebate or additional charges:

• Share purchase: $50
• Trading fee: 100 × 0.07 × 0.50 × 0.50 = $1.75
• Total cost: $51.75

Winning shares redeem for $1 each and losing shares for zero under Polymarket’s resolution rules. Holding these shares through resolution therefore gives an expected payout of 100 × q, where q is the probability of YES. Ignoring time value and resolution uncertainty, break-even requires:

100 × q = $51.75 → q = 51.75%

That does not establish that the event’s true probability is 51.75%. It establishes the fee-adjusted break-even threshold for this particular purchase. Forecast interpretation and trading cost are different measurements; see how prices become probabilities.

Costs beyond the platform fee

Polymarket says it charges no international-platform fee to deposit or withdraw USDC, but intermediaries such as Coinbase or MoonPay may charge their own fees, according to its fee documentation. Third-party trading integrations can also add builder taker fees, which the order documentation distinguishes from platform fees.

For an all-in calculation, start with actual fill prices, add trading and external charges, and subtract only applicable rebates. If you sell before resolution as a taker in a fee-enabled market, include the exit fee too. Spread and slippage affect the fill price: do not add them again if your calculation already uses that price. The all-in cost guide explains that accounting distinction. This is cost and forecast interpretation, not trading advice.