Polymarket vs Kalshi: Which Prediction Market Should You Use in 2026?

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Polymarket and Kalshi are the two largest prediction market platforms in the United States, and both let traders buy and sell contracts on the outcome of sports, politics, and other real world events instead of placing a traditional bet. 

Each platform is regulated as a designated contract market under the Commodity Futures Trading Commission, which sets them apart from offshore prediction sites and traditional sportbooks.

Sports have become the most heavily traded category on both platforms in 2026, with the World Cup driving record volume across Polymarket and Kalshi alike. This guide compares the two head-to-head on fees, market selection, legal access, and welcome offers so you can decide which platform fits how you want to trade.

What Is a Prediction Market?

A prediction market is a regulated exchange where traders buy and sell contracts tied to a real world outcome, such as which team wins a game or who wins an election. Each contract settles at $1 if the outcome occurs and $0 if it does not, and the contract price reflects the market's implied probability of that outcome happening.

Unlike a sportsbook, where an operator sets the odds, prediction markets let traders set prices by buying and selling against each other. Polymarket and Kalshi both operate this way, though they differ in fee structure, contract variety, and which states can access them.

Polymarket vs Kalshi: Quick Comparison

 Polymarket Overview

• Founded as a crypto native exchange, now operates a CFTC-regulated U.S. entity for domestic traders.
• Covers sports, politics, crypto, and culture markets, with sports and the World Cup driving the largest share of 2026 volume.
• Uses a probability weighted taker fee that is highest around 50 percent priced contracts and lower toward the extremes.
• Geopolitical and world event markets are currently fee free.
• Welcome Bonus: Deposit $20, Get $50 in Trading Bonus with Promo Code FOX

New users who sign up through FOX Sports can claim Deposit $20, Get $50 in Trading Bonus, one of the more generous welcome offers among U.S. prediction market platforms.

For more information, including terms and conditions and a full platform review, visit our Polymarket promo code page.

Kalshi Overview

• Was among the first prediction market platforms to secure full CFTC approval and operates entirely within U.S. financial regulation.
• Offers contracts across 17 sports plus politics, economics, and culture, with a dedicated sports tab for easier navigation.
• Uses a maker-taker fee model, with per contract pricing that peaks near 50 cent contracts and a separate 2 percent debit card deposit fee.
• Includes a built-in Ideas feed where traders share takes and discuss market moves.
• Welcome Bonus: Get $10 Bonus After Your First $10 Trade with Promo Code FOXSPORTS

Kalshi is currently offering new users a solid sign-up bonus: Get $10 Bonus After Your First $10 Trade

Visit our Kalshi promo code page for a full breakdown of the welcome bonus and a review of the platform.

Polymarket vs Kalshi: Fees Compared

Both platforms use a probability weighted fee structure where trading costs peak near the 50 percent mark and shrink as a contract's implied probability moves toward either extreme. 

Kalshi charges per contract taker fees plus a debit card deposit fee, while ACH, wire, and other funding methods typically avoid that charge. 

Polymarket's taker fees vary by category, with sports priced lower than crypto markets, and several categories, including geopolitics, currently carry no trading fee at all.

Neither platform charges deposit or withdrawal fees across the board, so the practical cost difference between Polymarket and Kalshi usually comes down to which categories you trade most and how you choose to fund your account.

Polymarket vs Kalshi: Sports Markets and Liquidity Compared

Sports have overtaken politics and crypto as the top category on both platforms in 2026, and both operators expanded coverage ahead of the FOX Sports exclusive broadcast window for the 2026 World Cup. 

Kalshi generally carries more total sports volume and spreads liquidity across a larger number of match-level contracts, which tends to produce tighter pricing on mainstream U.S. leagues like the NFL, NBA, and MLB. Polymarket concentrates liquidity into fewer, larger tournament scale markets, which has made its single biggest World Cup contract one of the most heavily traded prediction markets on either platform.

If you mostly trade major U.S. league markets, Kalshi's depth may produce steadier pricing. If you want broad, fast-moving coverage of international and niche events, Polymarket tends to list more of them.

Legal Status and Availability

Prediction markets occupy a different regulatory lane than traditional sports betting. Early in 2026, the CFTC classified prediction market contracts as swaps, placing them under federal oversight rather than state gambling law. 

Both Polymarket and Kalshi lean on that federal framework to offer sports and event contracts nationally, though the approach has drawn legal challenges in several states.

Kalshi has faced state level challenges and is currently unavailable in a handful of states, so availability can vary and is worth confirming directly on the platform before you sign up. Polymarket's return to the U.S. market has followed a similar regulatory path through its CFTC-designated entity. 

Because this area is actively evolving, always check each platform's current state availability before funding an account.

How to Get Started

1. Create an account on Polymarket or Kalshi and complete identity verification, which is required for CFTC-regulated platforms.
2. Fund your account using an available payment method; ACH or bank transfer typically avoids extra deposit fees.
3. Browse the sports tab or search for a specific game, league, or event.
4. Review the contract price, which reflects the market's implied probability, before you buy or sell.
5. Track your open positions and close them early if you want to lock in a gain or cut a loss, when liquidity allows.

Which Prediction Market Should You Choose?

Kalshi tends to suit traders who want deep liquidity on major U.S. sports, straightforward per-contract pricing, and a platform built specifically around U.S. financial regulation. 

Polymarket tends to suit traders who want broader event coverage, faster listings on trending topics, and a bigger welcome bonus to start with.

If you are weighing prediction markets against a traditional sportsbook, our best betting apps guide breaks down the top operators by state.

Responsible Gambling

Trading on a prediction market carries financial risk, and neither Polymarket nor Kalshi guarantees a return. If trading stops being fun or starts to feel like a way to solve money problems, the following resources can help.

• National Problem Gambling Helpline: Call or text 1-800-GAMBLER
• National Council on Problem Gambling: ncpgambling.org
• 1-800-GAMBLER Support Portal: 1800gambler.net
• Gamblers Anonymous: gamblersanonymous.org

Polymarket vs Kalshi FAQ

Is Polymarket or Kalshi better for sports trading?

Kalshi generally offers more sports contracts and deeper liquidity on major U.S. leagues, while Polymarket offers broader coverage of international and niche sporting events. Neither is universally better, it depends on what you want to trade.

Are Polymarket and Kalshi legal in the United States?

Both operate as CFTC-regulated designated contract markets, which allows them to offer contracts nationally under federal rather than state gambling law. Availability still varies by state, and legal challenges are ongoing in a few states.

Which platform has lower fees?

Both use a probability weighted fee model that peaks near 50 percent priced contracts. Kalshi's fees are charged per contract with an added debit card deposit fee, while Polymarket's taker fees vary by category and some categories are currently fee free.

Can I use both Polymarket and Kalshi at the same time?

Yes. Many traders maintain accounts on both platforms to compare pricing and take advantage of whichever offers better liquidity for a given event.

Do Polymarket and Kalshi offer the same sports?

There is significant overlap on major U.S. leagues, but Kalshi lists contracts across more total sports categories, while Polymarket tends to move faster on trending and international events.

What is the minimum deposit to start trading?

Minimums are low on both platforms, often as little as $10, though the amount needed to unlock a welcome bonus can differ. Check each platform's current promo terms before you fund your account.

Is my money safe on a prediction market?

Both platforms are regulated by the CFTC as designated contract markets, which requires them to meet federal standards for clearing and custody of funds. As with any trading platform, you can still lose the full value of a position.