How much is Kalshi's fee per contract?

At the standard sports rate it is 0.07 × P × (1 − P): 1.75¢ at 50¢, 1.68¢ at 60¢ and 0.63¢ at 10¢, rounded up. Some series, such as MLB games since August 7, 2026, use half that.

Does Kalshi charge fees on winnings?

No. The fee is charged when your order fills, and the fee schedule lists no settlement fee. You pay it whether the contract wins or loses.

Does Kalshi charge maker fees?

In series where the schedule lists a maker multiplier, yes: a resting order that fills pays M × 0.0175 × C × P × (1 − P), a quarter of the taker rate. Cancelling an order is free.

What are Polymarket US fees?

From September 25, 2026, the taker fee is 0.0695 × C × p × (1 − p) and makers earn a rebate at 0.0125, per Polymarket US's fee page.

Prediction markets

Kalshi fees explained, with the formula and net odds

Kalshi charges a fee when your order fills: 0.07 × contracts × price × (1 − price), times a per-market multiplier. It peaks at 1.75¢ per contract at 50¢ and turns a 60¢ contract from −150 into about −161.

Updated September 27, 2026 · TrueEdge Academy

Kalshi charges a trading fee when your order is filled, calculated as 0.07 × C × P × (1 − P), rounded up, where C is the number of contracts and P the price in dollars. Each market series also carries a multiplier M that scales it: 1 for most sports, 0.5 for MLB games since August 7, 2026. The fee is largest on 50¢ contracts, at 1.75¢ each, and it is paid whether the contract later wins or loses. On a 60¢ contract it moves the effective price from −150 to about −161. Everything below is from Kalshi's fee schedule (last updated July 7, 2026) and its public market API, read on September 27, 2026 — the schedule changes, so check it before relying on a rate.

Kalshi's formulas

Taker fee (you take a resting order): round up(M × 0.07 × C × P × (1 − P))
Maker fee (your resting order is filled): round up(M × 0.0175 × C × P × (1 − P))
Taker M by default: 1, unless the schedule lists another
Maker M by default: 0, unless the schedule lists one
Settlement fee: none

The July 7, 2026 schedule lists maker multipliers for many sports series, so resting orders there do pay the smaller maker fee. Cancelling a resting order costs nothing. Kalshi rounds the fee up (the schedule's own table shows a single 60¢ contract paying 2¢); on orders of 100+ contracts the rounding is a fraction of a cent.

Why the fee peaks at 50¢

P × (1 − P) is largest when P is 0.5 and shrinks toward both ends, so the fee follows the same curve: 1.75¢ per contract at 50¢, 1.68¢ at 60¢, 1.12¢ at 80¢, 0.63¢ at 10¢. A cleaner way to read it is as a share of what you stand to win. A contract bought at P profits 1 − P if it wins, and the fee is 0.07 × P of that profit. At 60¢ you pay 4.2% of your potential profit; at 20¢, 1.4%. But unlike a commission on winnings, it is charged up front, win or lose.

Worked: 100 contracts at 60¢, standard sports market (M = 1)

Contracts × price: 100 × $0.60 = $60.00
Fee: 0.07 × 100 × 0.60 × 0.40: $1.68
Total cost: $61.68
Pays if it wins: $100.00 (profit $38.32)
Net decimal odds: 100 ÷ 61.68: 1.621
Net American odds: −161 (vs −150 before the fee)

Illustration, not a live market.

Converting any price to net odds

The fee per contract is M × 0.07 × P × (1 − P), so a contract really costs P + M × 0.07 × P × (1 − P) and still pays $1. Net decimal odds are 1 divided by that cost; convert to American as usual. The fee matters most in the middle of the range and on long shots in proportional terms: at 10¢ it is 6.3% of your stake, at 90¢ 0.7%.

Gross and net odds at a 1× multiplier

30¢: +233 gross → +218 net (cost 31.47¢)
50¢: +100 gross → −107 net (cost 51.75¢)
60¢: −150 gross → −161 net (cost 61.68¢)
80¢: −400 gross → −430 net (cost 81.12¢)

Taker fees, per contract, before rounding. A 50¢ contract — an even-money bet on paper — is really −107 once the fee is in. In cents the fee peaks there; as a share of stake it is heaviest on long shots.

Worked: the same 60¢ trade on an MLB game (M = 0.5)

Fee: 0.5 × 0.07 × 100 × 0.60 × 0.40: $0.84
Total cost: $60.84
Net decimal odds: 100 ÷ 60.84: 1.644
Net American odds: −155

Kalshi's API lists the MLB game series at a 0.5 multiplier from August 7, 2026, and NFL, NBA, NHL and ATP match series at 1. Check the series before you assume a rate.

Polymarket US fees, for comparison

Polymarket US uses the same shape: fee = Θ × C × p × (1 − p). Its published taker Θ is 0.0695 exchange-wide from September 25, 2026, and makers receive a rebate at Θ = 0.0125. Fees are rounded to the cent using banker's rounding, combo trades have their own formula, and the schedule announces a higher table-tennis rate from September 30, 2026. At 60¢, 100 contracts cost $60 plus a $1.67 fee — within a cent of Kalshi's standard rate.

Letting the board do it

The Order Book computes every exchange leg with the venue's fee formula at fill and prints the return after fees; once you enter a stake, the fee in dollars appears under the card. The Order Book walkthrough works an example with the fee line and explains why the badge (priced on a $100 reference plan) and the line for your own stakes can differ slightly.

Frequently asked questions

How much is Kalshi's fee per contract?: At the standard sports rate it is 0.07 × P × (1 − P): 1.75¢ at 50¢, 1.68¢ at 60¢ and 0.63¢ at 10¢, rounded up. Some series, such as MLB games since August 7, 2026, use half that.
Does Kalshi charge fees on winnings?: No. The fee is charged when your order fills, and the fee schedule lists no settlement fee. You pay it whether the contract wins or loses.
Does Kalshi charge maker fees?: In series where the schedule lists a maker multiplier, yes: a resting order that fills pays M × 0.0175 × C × P × (1 − P), a quarter of the taker rate. Cancelling an order is free.
What are Polymarket US fees?: From September 25, 2026, the taker fee is 0.0695 × C × p × (1 − p) and makers earn a rebate at 0.0125, per Polymarket US's fee page.