Kalshi vs. Polymarket US fees: which is cheaper since November 2026
Both exchanges use the same shape of fee: a rate times the price times one minus the price, per contract, charged when your order takes a price that was already resting. The shape peaks at 50¢ and shrinks toward the edges. What differs is the rate.
The rates side by side
| Who pays | Kalshi | Polymarket US |
|---|---|---|
| Taker, ordinary account | 7% | 9.5% (under $10,000 of 30-day volume) |
| Taker, larger accounts | 7% | 8.5% / 7.5% / 6.95% as volume rises |
| Taker, new account’s first 7 days | 7% | 6.95% |
| Maker (resting order fills) | 1.75% on most sports and economics series; 0 on crypto minute and daily weather series | 0 |
| Rounding | up, per order | banker’s rounding |
Kalshi: fee schedule in effect since 7 July 2026. Polymarket US: schedule effective 6 November 2026.
What 100 contracts cost to take
| Price | Kalshi (7%) | Polymarket US (9.5%) | Polymarket US, first week (6.95%) |
|---|---|---|---|
| 10¢ or 90¢ | $0.63 | $0.86 | $0.63 |
| 20¢ or 80¢ | $1.12 | $1.52 | $1.11 |
| 30¢ or 70¢ | $1.47 | $2.00 | $1.46 |
| 40¢ or 60¢ | $1.68 | $2.28 | $1.67 |
| 50¢ | $1.75 | $2.38 | $1.74 |
The 9.5% rate is 36% more than Kalshi’s at every price; put the other way, Kalshi costs about 26% less. The first-week rate is the one most people see when they try the app, and it is the one that goes away.
Which is cheaper for you
- You take prices and trade under $10,000 a month (most people): Kalshi.
- Your first week on Polymarket US: about even; the gap opens on day 8.
- You only rest orders: Polymarket US charges makers nothing; Kalshi charges 1.75% on many sports and economics series and nothing on crypto and weather.
- Either way: the fee comes out of every trade, win or lose. A two-sided market returns your stake minus the fee on average, so the cheaper venue loses you money more slowly, not less surely. Our measurement of a popular retail rule lost 8 to 9 cents per dollar on both venues.
Your own trades, both venues · the full Kalshi schedule · the full Polymarket US schedule · a month at these fees
Sources read 8 November 2026: Kalshi fee schedule (kalshi.com/docs/kalshi-fee-schedule.pdf, effective 7 July 2026); Polymarket US fee schedule (docs.polymarket.us/fees, effective 6 November 2026). Figures computed from the published formulas, before rounding. Nothing here is financial advice.