What the current documentation states
On October 11, 2026, the documented formula is fee = C × feeRate × p × (1 − p), where C is share quantity and p is a price between 0 and 1. The table lists 0.07 for Crypto; 0.04 for Finance, Politics, Mentions and Tech; 0.05 for Sports, Economics, Culture, Weather and Other / General; and zero for Geopolitics. Maker fees are listed as zero. These are dated international-product parameters, not permanent fees for every platform.
Read the specific contract's current feeRate. The fee documentation denominates its calculation in USDC.
Maker and taker depend on execution
A maker leaves a resting offer for a later match; a taker trades against an existing offer. Immediately matched limit orders can also be takers. The label limit does not establish a zero fee: check execution and contract parameters.
Why 0.07 does not mean a 7% transaction fee
Consider an original arithmetic example: 20 shares at 0.40 with feeRate=0.07. The formula gives 20 × 0.07 × 0.40 × 0.60 = 0.336. The shares cost 8 before fees, so the calculated amount is 4.2% of that value. This illustrates different denominators; it is not an available quote or a final interface calculation.
Other components of cost
A spread is different from a fee: it describes the gap between buy and sell offers. A third-party intermediary or chosen transfer method may introduce another cost. Do not combine them into one advertised percentage without checking. Identify the amount’s currency, operation size and which components are already included in the displayed total.
How to check before comparing
Read the chosen contract’s current parameters and the official fee page. Compare the same size, price basis and complete cost components. If a parameter is missing or the page has changed, leave the result unknown. OddsAtlas does not treat probability conversion as a transaction-cost estimate or apply the international table to Polymarket US.
FAQ /
Common questions
Are all markets fee-free?
No. Parameters differ. A zero parameter for one category cannot be extended to other categories or to third-party costs.
Does this guide guarantee a future fee amount?
No. It explains the formula and an illustrative calculation as of the review date. Verify current contract parameters and the final calculation at the primary source.