Sources checked October 27, 2026
This guide was verified on October 27, 2026 against the Kalshi fee schedule page, the Kalshi fee schedule PDF, the Kalshi help articles on fees and card deposits, and the Polymarket fees documentation. Fee schedules change. Record the source, the date you read it, and any version shown, and treat the order preview for your exact market as authoritative.
The general formula, and why it is only a starting point
The general fee schedule PDF expresses the taker trading fee in dollars as M × 0.07 × C × P × (1 − P), where C is the number of contracts, P is the contract price in dollars, and M is a fee multiplier. It expresses a maker fee, where one applies, as M × 0.0175 × C × P × (1 − P). Only the schedule that applies to a specific series defines M, whether maker fees apply, and how rounding works. The live fee schedule page lists most markets with a multiplier of 1 and taker fees only, lists combos with maker fees at 50% of taker, and lists other series with additional fees or different multipliers. A single universal maker formula is therefore not appropriate. The Kalshi fees help article adds that maker fees are charged only when a resting order actually executes, not when it is cancelled.
Rounding: illustrative math versus your final quote
The PDF describes rounding the fee plus position cost to a centicent (one hundredth of a cent), while its example tables show totals rounded to whole cents. This guide does not resolve that difference. The numbers below are unrounded illustrations of the general formula with M = 1. Your final charge is whatever the order preview and the applicable schedule produce.
Illustrative examples (general formula, not live quotes)
These apply the general taker formula with M = 1 before any market-specific multiplier, exception, or rounding. They are not quotes for any live market.
- 100 contracts at $0.50: 0.07 × 100 × 0.50 × 0.50 = $1.75 taker fee.
- 100 contracts at $0.10: 0.07 × 100 × 0.10 × 0.90 = $0.63 taker fee.
- 1,000 contracts at $0.30: 0.07 × 1,000 × 0.30 × 0.70 = $14.70 taker fee.
- 10 contracts at $0.05: 0.07 × 10 × 0.05 × 0.95 = $0.03325 raw, unrounded. Check the final order preview for the charged amount.
- Where a maker fee applies under the general maker formula, 100 contracts at $0.50 would be 0.0175 × 100 × 0.50 × 0.50 = $0.4375 raw, unrounded. Many series charge no maker fee; check the applicable schedule.
Worked round trip, with denominators labelled
Illustration only, not a live quote: buy 100 contracts at $0.50 as a taker, then sell 100 at $0.50 as a taker, general formula, M = 1. Each leg is computed separately: $1.75 to buy and $1.75 to sell, so $3.50 in trading fees, or 3.5¢ per contract. Measured against the $50 entry cost (100 × $0.50), that is 7%. Measured against the $100 maximum payout (100 × $1.00), that is 3.5%. Say which denominator you mean whenever you quote a percentage. If the exit price differs from the entry price, the exit fee differs too; do not assume it equals the entry fee. This is not the same thing as sportsbook vig, which is built into quoted odds, and these figures do not show that any strategy is cheaper or profitable.
Funding and other non-trading costs
Per the fee schedule PDF, Kalshi charges no fee for ACH deposits or withdrawals, and no settlement or membership fees. The PDF lists a fee of up to 2% for debit card deposits, and the card deposits help article says debit deposits may incur a 2% processing fee; it also notes credit cards may be processed with varying fees and possible card-issuer charges. Third-party crypto or other funding routes can carry their own costs. Do not assume every funding method is free; check the method's terms at the time you use it. No settlement fee does not mean holding to settlement costs nothing: the entry fee, the spread you crossed, and any funding cost still apply.
Polymarket fees: check which product you mean
The current Polymarket fees documentation for the international product describes taker fees that depend on market category, calculated as C × feeRate × p × (1 − p), with makers not charged fees; some categories are listed as fee-free and combos have their own rate. It does not support a universal claim that Polymarket is free, nor a universal gas charge for placing or cancelling off-chain orders. Polymarket US is a separate product with its own documentation; do not apply the international fee table to it. For product, access, and eligibility differences, see Kalshi vs Polymarket and the regulatory notes in How Kalshi works. For the vocabulary — notional, spread, slippage — see our prediction market terms glossary.
Fill-in cost worksheet
Copy these fields for each trade you are estimating. Compute each leg separately from the executable prices you actually see, and do not assume half the spread or a doubled entry fee. If anything is unknown, write unknown.
Scroll the table sideways if needed.
| Field | What to record |
|---|---|
| Product and market | Exact product and domain, market ticker or name, series, and the fee schedule source, date read, and version that applies to it. |
| Entry price and size | The executable buy price and contract count you would actually fill at, not the mid-price. |
| Entry fee | Whether the entry fills as taker or maker, the rate and multiplier from the applicable schedule, and the resulting fee for that leg. |
| Exit assumption and fee | The assumed exit price and size (or holding to settlement), and the fee for that leg computed at that exit price. Settlement itself carries no fee per the PDF. |
| Spread, depth, and partial fills | Current best bid and ask, visible depth at your size, and what happens if only part of the order fills. |
| Funding cost | Deposit and withdrawal method and any fee it carries, including debit processing or third-party charges. |
| Expected cash spent and proceeds | Total cash spent on entry including fees, and expected net proceeds from the exit or from settlement after fees. Compare with the final order preview. |
Before you place an order
- Confirm the fee schedule source, the date you read it, and any version shown.
- Confirm the series, market rules, multiplier, and whether a maker fee applies.
- Read the final order preview and compare its fee and total cost with your worksheet.
- Verify current terms before trading; this guide is not trading advice and makes no profit or cost-saving promise.
If an order outcome is uncertain
If an order timed out or you cannot tell whether it filled, do not repeat it until you have reconciled your open orders, fills, and positions; a repeat can double your exposure and your fees. Use the decision checklist in the troubleshooting guide.