Kalshi, Polymarket and Polymarket US, compared
Three exchanges, three fee schedules. The fee row is computed from the same code that prices positions in the terminal.
Side by side
| Kalshi | Polymarket | Polymarket US | |
|---|---|---|---|
| Taker fee, 100 contracts at 50¢ | $1.75 | Free to $1.75 | $1.74 |
| How the fee is set | One formula, 0.07 for most series | By category, set per market at listing | One rate for every market |
| Fee when a contract settles | None | None | None (modeled) |
| Smallest price step | 0.1¢ under 10¢ and over 90¢, 1¢ between | 0.1¢ | 1¢ |
| Settles in | US dollars | USDC | US dollars |
Is Polymarket US the same as Polymarket?
No. They are separate exchanges with separate accounts, order books, fee schedules and price grids. On one NFL game, none of the 1,076 markets on Polymarket US matched a market on Polymarket.
Which has the lower fee at 50¢?
On a 100-contract position at 50¢, Kalshi charges $1.75, Polymarket charges between nothing and $1.75 depending on category ($1.00 for politics, $1.25 for sports), and Polymarket US charges $1.74.
Do Kalshi or Polymarket charge a fee when a contract settles?
Neither Kalshi nor Polymarket charges a fee at settlement; you pay a fee only when you buy, and again if you sell before settlement.
How far apart are Kalshi and Polymarket prices on the same game?
Usually less than a cent. Over a week of in-play NFL, MLB and WNBA games in October, the median gap between Kalshi and Polymarket US for the same team was 0.1 to 0.25¢, and a gap of 5¢ or more showed up in fewer than 1% of minutes.
Do Kalshi and Polymarket handle postponed games the same way?
No. Kalshi and Polymarket US wait a fixed window for a makeup game (48 hours to two weeks, depending on the sport and venue) and then settle at a fair price; Polymarket waits until the game is played.
Kalshi fee calculator →Polymarket fee calculator →Polymarket US vs Polymarket →Postponed games →
Informational only, not trading advice. Confirm rates against your own fills.
The terminal puts all three on one line for the same outcome, with the gap in cents and the fees subtracted.
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