Kalshi vs Polymarket Fees: What You Actually Pay in 2026

Neither platform can be accurately summarized by one flat trading fee across every market. Both Kalshi and Polymarket tie trading costs to the contract’s probability, but they use different schedules, coefficients and order-book rules.

Kalshi’s main fee schedule uses a probability-based curve. Polymarket’s global fee schedule also uses a probability-based formula, but its fee rate changes according to the market category. Polymarket also operates a separate U.S. exchange product with its own fee schedule.

As a result, the same 100-contract order can cost a few cents or around $1.75 in standard trading fees, depending on the contract price, market category, order type and applicable product multiplier. Understanding that structure(not memorising a single percentage) is what determines which platform is cheaper for the specific trade in front of you.

How Kalshi Prices Its Fees

Kalshi uses a standard probability-based formula across most of its exchange:

• Fee = round up(M×0.07×C×P×(1−P)M \times 0.07 \times C \times P \times (1-P)M×0.07×C×P×(1−P))

In this formula, CCC is the number of contracts, PPP is the contract price in dollars, and MMM is the applicable product multiplier. The standard multiplier is generally 1, although specific products can use different maker or taker multipliers.

Because the formula multiplies the price by its inverse, the fee peaks at the 50-cent mark and falls toward both extremes. A contract sitting at a coin flip costs the most to trade. A near-lock at 95 cents or a longshot at 5 cents costs much less before rounding.

Run the numbers and the shape becomes clear. At 50 cents, the theoretical standard taker fee per contract is:

• 0.07 × 0.50 × 0.50 = 0.0175

• That is about 1.75 cents per contract, meaning a 100-contract order costs roughly $1.75 before any order-level rounding.

• At 20 cents:

• 0.07 × 0.20 × 0.80 = 0.0112

• That is about 1.12 cents per contract, or roughly $1.12 for 100 contracts.

• At 90 cents:

• 0.07 × 0.90 × 0.10 = 0.0063

• That is about 0.63 cents per contract, or approximately $0.63 for 100 contracts before order-level rounding.

Kalshi’s billing rules round fees up according to the total order calculation, so the final amount shown on the order ticket may differ slightly from a simple multiplication of the per-contract figure.

Maker orders(the limit orders that add liquidity instead of taking it) generally use a lower coefficient of 0.0175, which is one-quarter of the standard 0.07 taker coefficient. That means makers usually receive a substantial discount, although the fee is not automatically waived and product-specific multipliers can apply.

Some markets sit outside the standard schedule entirely. Kalshi’s July 2026 fee schedule confirms that individual products can have their own maker and taker multipliers. Therefore, the 0.07 formula is a starting point rather than a guarantee for every contract type. Check the order ticket before submitting, particularly when trading non-standard products.

How Polymarket Prices Its Fees

Polymarket operated for much of its history with fewer trading fees across many categories. That changed in stages during 2026. On March 30, Polymarket introduced Fee Structure V2, expanding taker fees across most paid market categories.

Polymarket Global calculates fees using this formula:

• Fee = C×feeRate×P×(1−P)C \times \text{feeRate} \times P \times (1-P)C×feeRate×P×(1−P)

Here, CCC is the number of shares traded, PPP is the share price, and the fee rate depends on the market categories.

The current global schedule sets the following base rates:

• 0.07 for crypto markets.

• 0.04 for finance, politics, tech and mentions markets.

• 0.05 for economics, culture, weather and sports markets.

• 0 for geopolitics and world-events markets, which remain fee free.

Earlier 2026 reporting listed sports markets at a 0.03 rate, while the current schedule lists sports at 0.05. Traders should therefore rely on the current market interface and fee documentation rather than older comparisons.

Makers pay nothing on Polymarket Global regardless of category. The fees collected from takers help fund a rebate programme for eligible market makers, with the rebate percentage varying by market type.

At a 50-cent contract price, Polymarket’s category rates produce the following approximate fees:

The calculation is straightforward. For a 0.05 category, for example:

• 0.05 × 0.50 × 0.50 = 0.0125

• That equals approximately 1.25 cents per contract, or $1.25 for 100 contracts.

Polymarket also operates a separate U.S. exchange product with its own fee schedule. The published U.S. schedule uses a 0.06 probability-weighted taker coefficient, producing a maximum taker fee of approximately $1.50 per 100 contracts at a 50-cent price. Makers receive a rebate calculated using a 0.0125 coefficient, with additional volume-based rebates potentially available under the platform’s schedule.

The U.S. product therefore has a meaningfully different cost profile from Polymarket Global. Which schedule applies depends on the specific Polymarket product available to the trader.

Side by Side at the Same Price Point

At a 50-cent contract(a coin-flip market), the two platforms do not line up perfectly.

Kalshi’s standard taker fee is approximately 1.75 cents per contract, or about $1.75 for 100 contracts at the standard multiplier.

Polymarket Global’s fee depends on the category:

• A 0.04 category costs about 1 cent per contract.

• A 0.05 category costs about 1.25 cents per contract.

• A 0.07 crypto category costs about 1.75 cents per contract.

• Geopolitics and world-events markets can remain fee free.

At a 50-cent price, Polymarket Global is therefore cheaper than Kalshi in 0.04 and 0.05 categories, equal to Kalshi in a 0.07 category, and cheaper still in fee-free categories. Kalshi can remain competitive at other price points, particularly where its product multiplier, liquidity and execution quality compare favourably.

Where the gap really opens up is on the maker side.

A 90-cent contract on Kalshi has a theoretical standard taker fee of about 0.63 cents per contract before order-level rounding. On Polymarket Global, a maker order costs nothing, and eligible makers may also receive rebates. That is a structural advantage Kalshi does not fully match because its maker discount reduces the fee but does not generally eliminate it.

For a trader who mostly uses limit orders and lets them fill, rather than crossing the spread with marketable orders, Polymarket’s zero maker fee is one of the biggest cost differences between the two platforms.

The Costs Neither Platform Puts on the Fee Page

Trading fees are only part of the real cost.

Kalshi supports ACH bank transfers without a platform fee. Debit-card deposits can carry a processing fee of up to approximately 2%, according to Kalshi’s published fee schedule. Traders should check the current funding screen because payment-method charges can vary.

Polymarket Global does not charge a platform fee to deposit or withdraw USDC. However, users may still incur costs from card on-ramps, crypto exchanges, wallets, bridges, blockchain networks and cash-out providers. Those charges vary significantly according to the provider, country, payment method, network conditions and withdrawal route.

The exact cost of converting cash to USDC cannot be reduced to one universal range. A card on-ramp may charge a percentage fee, while a crypto exchange or bank withdrawal may use a different combination of spreads, fixed charges and network costs. Similarly, bridging USDC between networks is not always necessary and may involve different costs depending on the route selected.

That asymmetry can matter more than it appears on paper. A trader who deposits $500, trades once and withdraws may pay more in third-party funding and cash-out costs than in platform trading fees. The result depends on the provider and route, so this should be treated as a possibility rather than a guaranteed outcome.

A trader who deposits once, keeps capital on the platform and trades actively for months may spread those conversion costs across many transactions. Even then, the costs are not necessarily insignificant; they are simply paid less frequently than trading fees.

Sports Markets Specifically

Both platforms have changed their sports fee structures, and the current comparison is closer than some older guides suggest.

Kalshi expanded its sports-event-contract offering during 2025 and generally applies its standard fee formula to many sports markets. The applicable product multiplier should still be checked because Kalshi’s fee schedule allows individual series to use different maker and taker multipliers.

Polymarket’s current global sports rate is 0.05. Earlier 2026 reporting listed a 0.03 rate, so the increase has narrowed the previous advantage for sports traders.

At a 50-cent sports-market price, Kalshi’s standard taker fee is approximately:

0.07 × 0.50 × 0.50 = 0.0175

That equals about 1.75 cents per contract, or $1.75 for 100 contracts when the standard multiplier applies.

Polymarket’s sports fee is:

0.05 × 0.50 × 0.50 = 0.0125

That equals about 1.25 cents per contract, or $1.25 for 100 contracts on Polymarket Global.

If you are comparing the platforms primarily for NFL, NBA, soccer or other sports contracts, check the current fee displayed for the specific market. Older comparisons may show the previous Polymarket sports rate, while Kalshi’s product-specific multiplier can also affect the final amount.

Which Platform Is Actually Cheaper?

The honest answer is that it depends on your order type, market category, contract price, liquidity and how often you move money on and off the platform.

Maker orders generally favour Polymarket Global, because makers pay no trading fee and may qualify for rebates.

Kalshi can be convenient for traders using ACH, since ACH funding is free and its standard fee formula is relatively easy to calculate. However, the final cost still depends on the contract, order type, product multiplier and execution conditions.

Polymarket can be less efficient for small, one-time deposits and withdrawals if third-party on-ramp and cash-out charges are high relative to the amount being traded. That outcome depends on the chosen payment and withdrawal providers.

For 50-cent taker orders, Polymarket Global is cheaper than standard Kalshi in 0.04 and 0.05 categories, roughly equal in 0.07 crypto markets, and fee-free in geopolitics and world-events markets. At other prices, or when spreads and liquidity differ, the cheaper platform may change.

Both fee schedules have changed during 2026, and further adjustments remain possible. The number that matters is not only the number in this article. It is the fee shown on the order ticket in front of you when you place the trade—and checking it there every time costs nothing at all.