How Do Polymarket Fees Work? The Formula Explained

On March 30, 2026, Polymarket expanded its fee structure from just Crypto and Sports to nearly every market category on the platform. The change was logged as "Fee Structure V2" in the documentation changelog. Rates have been adjusted since; the numbers below reflect Polymarket's documentation as of October 2026.

The fee model is not a flat percentage. It is a probability-weighted curve that charges the most when uncertainty is highest and the least when outcomes are nearly certain. That design choice has real implications for how and where systematic traders should operate.

How Polymarket Fees Are Calculated: The Formula

Polymarket calculates taker fees using:

fee = C × feeRate × p × (1 - p)

Where C is the number of shares traded, feeRate is a category-specific constant, and p is the share price (which represents the implied probability of the outcome).

Makers pay zero fees. Only takers - traders who lift existing orders from the book - are charged.

The critical term is p × (1 - p). This is the variance of a Bernoulli distribution. It peaks at p = 0.50 where it equals 0.25, and it approaches zero as p moves toward 0 or 1.

A trade at 50¢ generates the maximum fee. A trade at 10¢ or 90¢ generates 36% of the maximum. A trade at 5¢ or 95¢ generates just 19%.

Category Fee Rates

Each market category has its own feeRate parameter (as of October 2026):

Combos (multi-leg positions) are charged their own rate of 0.05, regardless of which categories their legs come from.

The taker pays the full fee. Part of it is then passed on to makers through the Maker Rebates program: 20% in Crypto, 15% in Sports and 25% in the other fee-enabled categories (0% on Combos). Sports changed on July 10, 2026, when its feeRate rose from 0.03 to 0.05 and its maker rebate fell from 25% to 15%.

Geopolitical and world events markets remain completely fee-free. Polymarket states that it does not charge fees or profit from trading activity on those markets.

The Fee Curve Shape

The p × (1 - p) term creates a symmetric parabola. A trade at 30¢ generates the exact same dollar fee as a trade at 70¢. Per share, the shape means:

• High-uncertainty markets (40¢–60¢): Maximum fee extraction. This is where the platform generates the most revenue per share traded.
• Moderate-probability markets (20¢–40¢ or 60¢–80¢): Fees drop meaningfully. A trade at 20¢ costs 64% of the 50¢ fee.
• Extreme prices (<10¢ or >90¢): The fee per share becomes small. A trade at 5¢ costs just 19% of the peak.

For a 100-share Crypto trade, this translates to $1.75 at 50¢, $1.12 at 20¢, and $0.33 at 5¢.

There is a catch. Measured against the money you put in, the fee is feeRate × (1 - p), so cheap shares are the expensive ones. Buying a Crypto share at 95¢ costs 0.35% of the trade value; buying one at 5¢ costs 6.65%. Traders who buy near-certain outcomes pay structurally less than traders in contested markets. Traders who buy longshots pay the most of anyone, relative to their stake.

Fee Precision and Edge Cases

Fees are rounded to 5 decimal places. The smallest possible fee is 0.00001 (in pUSD, Polymarket's USDC-backed collateral token since its April 2026 CLOB V2 upgrade). Anything below that rounds to zero, which means very small trades at extreme prices may incur no fee at all.

Fees are set by the protocol and applied at match time. You do not include a fee in your signed order.

Not every market in a fee-enabled category charges fees. When fees were rolled out, they applied to newly created markets, and older markets kept trading fee-free. The feesEnabled flag and the feeSchedule object on the market are the authoritative check.

Maker Rebates: The Other Side

Polymarket does not keep all collected fees. Taker fees fund a Maker Rebates program that redistributes a portion daily in pUSD to liquidity providers.

Rebates are weighted by the same fee curve: each filled maker order earns a "fee equivalent" of C × feeRate × p × (1 - p), and your daily rebate is your share of the market's total fee equivalent. You compete only with other makers in the same market, not across the platform. Payouts require at least $1 in accrued rebates.

Since May 28, 2026, takers can also earn part of their fees back through a tiered Taker Rebate Program. Rebates run from 3% (Bronze) to 50% (Obsidian), based on 30-day "weighted volume" that counts Crypto trades most and Sports trades least.

The maker rebate creates a two-sided incentive: takers pay fees that fund makers who provide the liquidity takers need. Deeper books mean tighter spreads, which theoretically offsets some of the fee cost through better execution prices.

What This Means for Systematic Strategies

The fee structure creates distinct zones of fee efficiency:

1. Low-fee zone (p < 0.15 or p > 0.85): The fee per share is about half the peak or less. Strategies that trade outcomes the market prices as very likely or very unlikely operate in the cheapest part of the curve per share. Per dollar invested, only the expensive side is cheap: buying at 90¢ costs about a ninth as much as buying at 10¢, relative to stake.
2. Peak-fee zone (0.40 < p < 0.60): Maximum fee extraction. Strategies that trade contested outcomes pay the full cost. Scalping in this zone requires enough edge to clear the fee hurdle on every round trip.
3. Category differences: Crypto markets carry 1.75× the fee rate of Finance, Politics, Mentions and Tech markets, and 1.4× the rate of Sports and the other 0.05 categories. A systematic trader running the same strategy across categories will see meaningfully different returns purely from the fee differential.
4. Maker advantage: Since makers pay zero fees and receive rebates, any strategy that can express its views through limit orders rather than market orders transforms from fee-payer to fee-receiver. That is the largest structural advantage in the fee design.

The Revenue Math

We have not found an official fee revenue figure from Polymarket, but the formula gives the order of magnitude. Measured against trade value, the fee is feeRate × (1 - p): 2% to 3.5% at 50¢ depending on category, falling toward zero as the price approaches $1. Every $100 million of taker volume at 50¢ in a 0.04 category therefore generates $2 million in fees, before maker and taker rebates. Actual revenue depends on how volume is spread across the fee curve and on how much of it is in fee-free markets.

For context, Polymarket charged no trading fees for most of its existence. The fee rollout that began with 15-minute Crypto markets in January 2026 and expanded to nearly all categories by March 30 represents the platform's first real monetization model.

FAQ

Does Polymarket charge fees on every market?

No. Geopolitics and world events markets remain fee-free. Fees also apply only to markets deployed on or after their category's activation date, so older markets in a fee-enabled category still trade without fees. The feesEnabled flag on the market object is the authoritative check before assuming a fee applies.

How much are Polymarket fees?

It depends on category and price. As of October 2026 the feeRate ranges from 0.04 for Finance, Politics, Mentions and Tech to 0.07 for Crypto, and the fee scales with p × (1 - p). A 100-share Crypto trade costs $1.75 at 50¢, $1.12 at 20¢, and $0.33 at 5¢. Peak cost per share always lands at 50¢ odds.

Do makers pay fees on Polymarket?

No. Only takers - traders who lift existing orders from the book - pay fees. Makers pay zero and additionally receive a share of the Maker Rebates pool, which redistributes 20% of collected fees in Crypto, 15% in Sports and 25% in other fee-enabled categories. Rebates are paid daily in pUSD, proportional to your share of executed maker liquidity.

Why do Polymarket fees cost more at 50/50 odds?

The formula multiplies by p × (1 - p), the variance of a Bernoulli distribution. That term peaks at 0.25 when p = 0.50 and falls toward zero at the extremes. The design ties cost to uncertainty rather than notional value, so contested markets pay the most and near-settled outcomes pay almost nothing.

Observations

The fee formula is elegant. By tying cost to uncertainty rather than notional value, it charges the most where information is most valuable and the least where outcomes are already decided.

For systematic traders, the implications are structural:

• Per share, trades near the extremes pay less than contested-outcome trades; per dollar, buying longshots is the most expensive trade on the platform
• Maker strategies receive rebates; taker strategies absorb the cost, minus any tier rebate
• Category selection affects returns independently of prediction accuracy
• Geopolitical markets remain a fee-free zone for any strategy that can find edge there

The fee structure is not static. Polymarket's changelog shows fees expanding category by category since January 2026 and the Sports rate changing in July 2026, and since March 31, 2026 it has told API users to calculate fees from the feeSchedule object on each market. That object, not a hardcoded table, is the source of truth.

None of this is a recommendation to trade on Polymarket or any prediction market. These are observations about fee mechanics and their mathematical properties.

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