Polymarket US fees, explained: what you actually pay per trade (and the 6 November 2026 change)
Polymarket US charges a fee only on orders that take liquidity, and the fee is largest in the middle of the price range. The formula, from the venue’s published schedule:
Fee = Θ × C × p × (1 − p), where C is the number of shares, p is the price in dollars, and Θ is a coefficient set by your trailing 30-day taker volume.
The coefficient since 6 November 2026
| Your 30-day taker volume | Θ | Fee on a 50¢ share | On 100 shares at 50¢ |
|---|---|---|---|
| New account, days 1 to 7 | 6.95% | 1.74¢ | $1.74 |
| Under $10,000 (most people) | 9.5% | 2.38¢ | $2.38 |
| $10,000 to $50,000 | 8.5% | 2.13¢ | $2.13 |
| $50,000 to $250,000 | 7.5% | 1.88¢ | $1.88 |
| $250,000 and up | 6.95% | 1.74¢ | $1.74 |
Before 6 November everyone paid 6.95%. The change raised the fee for an ordinary account by 37% and left the old rate for the largest accounts and for a new account’s first week. Volume is measured in dollars paid or received, not face value: a buy counts C × p, a sell counts C × (1 − p). Tiers reset daily on a rolling 30-day window of completed days.
Why the middle costs the most
p × (1 − p) peaks at p = 0.5 and falls toward zero at either end:
| Price | p × (1 − p) | Fee per share at 9.5% | Fee as % of what you pay |
|---|---|---|---|
| 10¢ | 0.09 | 0.86¢ | 8.6% |
| 30¢ | 0.21 | 2.00¢ | 6.7% |
| 50¢ | 0.25 | 2.38¢ | 4.8% |
| 70¢ | 0.21 | 2.00¢ | 2.9% |
| 90¢ | 0.09 | 0.86¢ | 1.0% |
Measured against what you put in, the fee is heaviest on cheap longshots: a 10¢ share costs 8.6% of your stake in fees before the outcome is known.
What it does to your break-even
A share bought at p pays $1 if it wins and $0 if it loses. With no fee you break even at a win rate equal to the price. With the fee you need:
Break-even win rate = p + Θ × p × (1 − p) (holding to settlement; trading out early pays the fee again)
At 50¢ and 9.5% that is 52.4% rather than 50%. At 9.5% across a month of 87 fifty-dollar trades at 50¢, the fees alone are about $207, whatever the outcomes. See your own numbers, or watch a few hundred simulated careers play out.
The one honest way to pay less
Resting orders pay nothing. If you place a limit order below the current offer and wait, the fee is zero when it fills. The cost is uncertainty: the market may move away and the order may never fill, and the people quoting both sides for a living are better at this than you are. Rebates exist for very large makers (from $10 million of monthly maker volume), and taker rebates start at $250,000 of monthly taker volume; neither applies to an ordinary account.
Rounding and small trades
Fees round to the nearest cent using banker’s rounding (half to even), and on small trades they can round to $0.00: 1 share at 50¢ carries a 2.4¢ fee that rounds to 2¢; 1 share at 5¢ carries a 0.45¢ fee that rounds to $0.00. Combo (multi-leg) orders use a separate, higher formula.
Source: Polymarket US fee schedule, docs.polymarket.us/fees, read 8 November 2026. Fees change; the date on this page is when we last checked. Nothing here is investment advice.