Guide
Kalshi fees explained, with examples
Kalshi charges a trading fee that depends on the price and the number of contracts. It's highest at 50¢ and lowest near 1¢ or 99¢. Here is the formula, a table of real numbers, and what it means for arbitrage.
The formula
Fee = 0.07 × contracts × P × (1 − P), rounded up to the next cent, per order.
P is the price in dollars (47¢ = 0.47). This is the taker fee for orders that fill right away. Under the fee schedule effective July 7, 2026 the same 0.07 applies across series; a few long-dated series charge no taker fee. Always check the market page, since Kalshi can change its schedule.
Kalshi fee table
| Price | 1 contract | 10 | 100 | 1,000 |
|---|---|---|---|---|
| 5¢ | $0.01 | $0.04 | $0.34 | $3.33 |
| 10¢ | $0.01 | $0.07 | $0.63 | $6.30 |
| 25¢ | $0.02 | $0.14 | $1.32 | $13.13 |
| 50¢ | $0.02 | $0.18 | $1.75 | $17.50 |
| 75¢ | $0.02 | $0.14 | $1.32 | $13.13 |
| 90¢ | $0.01 | $0.07 | $0.63 | $6.30 |
| 95¢ | $0.01 | $0.04 | $0.34 | $3.33 |
Computed with the formula above, rounded up to the cent per order.
What it means in practice
- The fee peaks at 50¢: $1.75 per 100 contracts, or 1.75¢ each. Near 5¢ or 95¢ it's about a third of a cent each.
- Small orders pay more per contract. Rounding up to the cent means 1 contract at 5¢ costs a full cent in fees, 20% of its price.
- It's charged per order, not per trade idea. Splitting one buy into many small orders adds rounding on each one.
- No fee to hold or settle. The fee is charged when you buy; a winning contract pays the full $1.
Fees and arbitrage
For a two-sided trade, add the fee on each side to the prices. A Kalshi YES at 47¢ plus a fee-free Polymarket NO at 50¢ is 97¢, plus about 1.75¢ in Kalshi fees: still under $1, so about $1.25 profit per 100 pairs. The same gap against Polymarket US, which also charges a fee, can lose money. Run your own numbers in the calculator.
Common questions
How much does Kalshi charge per trade?
0.07 times contracts times price times (1 minus price), rounded up to the cent, per order. At 50 cents that's 1.75 cents per contract; near 5 or 95 cents it's about a third of a cent.
Does Kalshi charge a fee when a contract settles?
No. The trading fee is charged when the order fills. A winning contract pays out the full $1.
Why do small Kalshi orders pay more in fees?
Each order's fee is rounded up to the next cent, so tiny orders pay a full cent even when the formula gives a fraction of one.
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