Kalshi Fee Schedule: How Trading Fees Are Set

Kalshi charges a per-contract trading fee that is not a flat percentage. It follows a curve that peaks when a contract trades near 50 cents and falls toward both ends of the price range, so the single most expensive place to trade is a genuine coin-flip market, while buying a near-certain outcome at 95 cents or a long-shot at 5 cents costs far less per contract.

Kalshi publishes its trading fee formula in its official fee schedule and documentation, and the shape of the curve is the part most first-time traders miss. What follows walks through the formula, the dollar cost at different prices, and the fees that sit outside the trading fee itself.

Key takeaways

• Kalshi's general trading fee is calculated from a formula tied to the contract's price, not a flat cut of your stake.
• The fee per contract is highest near a 50-cent price (maximum uncertainty) and drops as a market approaches 0 cents or 100 cents.
• Contracts settle at either $1 (the outcome happened) or $0 (it did not), so the price in cents is effectively the market's implied probability.
• Trading fees are separate from other charges such as withdrawal fees, and some maker-taker style structures and promotions can vary by market.
• Always confirm the current numbers against Kalshi's own fee schedule, because the coefficients and rounding rules can change.

Why the fee is a curve, not a flat rate

A Kalshi contract is a yes-or-no event contract. You are buying a claim that pays $1 if a stated outcome occurs and $0 if it does not, a fixed-payout contract: it settles at a set amount if the stated outcome occurs, with an order book on a federally regulated exchange as the counterparty. Because every contract resolves to either 100 cents or 0 cents, the trading price in cents behaves like the market's implied probability. A contract at 50 cents means the market sees the outcome as a coin flip. A contract at 95 cents means the market treats it as nearly certain.

Kalshi's trading fee is calculated from that price. The published formula multiplies a fixed coefficient by the contract count and by a term of the form price times (one minus price), where price is expressed as a decimal. That product, price times (one minus price), is a parabola: it is largest at 0.50 (where it equals 0.25) and shrinks toward zero as the price approaches 0 or 1. The fee tracks how uncertain the market is, and the peak cost lands squarely on the fifty-fifty contracts.

What you actually pay: worked examples

The general trading fee Kalshi documents takes the form fee = round up ( coefficient x contracts x price x (1 - price) ), with price as a decimal between 0 and 1. The table below shows how the price times (one minus price) term behaves at different prices. The exact fee depends on the live coefficient and rounding rule, so confirm those on Kalshi's own fee documentation before relying on precise cents.

The per-contract fee looks small, but it scales with the number of contracts and it is charged on both entry and exit. Contracts bought near 50 cents carry the highest possible fee term at 0.25, while contracts bought near 90 cents see that term collapse to 0.09, so the fee on the same dollar volume is a fraction of the coin-flip case. The cost of trading is not uniform; it concentrates where the market is most uncertain.

Per contract, the fee term is largest near 50 cents and smallest near the ends of the price range, even at the same dollar volume. The deeper walkthrough of that peak lives in why the cost peaks near 50 cents.

The fees that are not the trading fee

The trading fee is the one most people mean by the Kalshi fee schedule, but it is not the only charge. Kalshi's documentation also covers settlement handling, and separate policies apply to moving money in and out of an account. Deposits and withdrawals can carry their own costs depending on the method, and those are set independently of the price-curve trading fee. Some markets and member programs can also carry different fee treatment, so the coefficient that applies to a given contract is not always the standard one.

For traders reaching Kalshi programmatically rather than through the app, the fee mechanics are identical, but the account requirements around identity verification and access differ. That side of the picture is covered in what KYC and fees mean for API access.

Reading fee-bearing activity as data

A single trader can read their own fees off a receipt. Comparing fee-bearing activity across a whole prediction market, or across several venues, is harder, because the raw records do not arrive in one shape. To line up a trade on one platform with a trade on another, the same event has to resolve to the same fields: the market identifier, the outcome, the contract price, the quantity, the timestamp, and the resolved settlement value. Without that normalization, a coin-flip contract at one venue and a coin-flip contract at another are not directly comparable even though the underlying economics are the same.

Allium standardizes prediction-market records into consistent fields so pricing, volume, and settlement can be read the same way across sources, and publishes Kalshi datasets alongside broader prediction market data. Allium is a data layer used by institutions, researchers, and newsrooms to read these markets. It is not an exchange, broker, or advisor, and it does not set or collect the fees described here.

Where the numbers can shift

Fee schedules on regulated exchanges are not permanent. The coefficient, the rounding rule, and the treatment of specific market categories are all things Kalshi can adjust, and it has revised fee terms before. Treat any specific cent figure as an illustration of the curve's shape rather than a locked-in quote. The fee that applies is the one on Kalshi's schedule at the moment of the trade, because the exchange's own documentation is the authority on what applies to your order.

Frequently asked questions

Why is the Kalshi fee highest at 50 cents?

The trading fee formula includes a price times (one minus price) term, which is a parabola that peaks at a decimal price of 0.50. Because a 50-cent contract represents maximum uncertainty (a coin flip), that is where the per-contract fee is largest. As a contract's price moves toward 0 cents or 100 cents, that term shrinks and the fee falls.

Does Kalshi charge a fee on both buying and selling?

Yes. The trading fee is applied to fills, so entering a position and exiting it before settlement are separate fee-bearing actions. Holding a contract to settlement rather than selling it early can change how many fee events you incur. Confirm the current treatment on Kalshi's fee documentation.

Is the Kalshi trading fee a flat percentage of my stake?

No. It is calculated from a formula tied to the contract's price rather than a flat cut of the dollar amount. Two positions of the same dollar size can carry different fees depending on the price at which the contracts trade, with coin-flip prices costing the most per contract.

Are deposits and withdrawals covered by the same fee schedule?

No. Moving money into and out of a Kalshi account is governed by separate policies from the per-contract trading fee, and costs can depend on the method used. Check Kalshi's own documentation for current deposit and withdrawal terms.

Can the Kalshi fee schedule change?

Yes. The coefficient, rounding rules, and category-specific treatment can all be revised by the exchange, and fee terms have changed before. Any specific cent figure should be treated as an illustration of the curve rather than a permanent quote, and priced against the live fee schedule before trading.

Interested in learning more about Allium’s prediction market data? Speak to someone on the team.

Allium provides onchain data infrastructure. Companies named in this article may be Allium customers, prospects or commercial counterparties. This article is informational only and is not investment, legal or tax advice. Data and information last reviewed: September 23, 2026.