Polymarket vs Kalshi: Overview

Polymarket launched in 2020 under founder and CEO Shayne Coplan. It runs an international site that settles trades on Polygon and a separate US exchange. Polymarket US is supervised by the Commodity Futures Trading Commission (CFTC), the US derivatives regulator. A $1 billion round reported on September 1, 2026, valued the company at $21 billion.

Tarek Mansour and Luana Lopes Lara founded Kalshi in 2018. CFTC approval as a regulated exchange followed in 2020. The regulator registered its clearinghouse, Kalshi Klear, in 2024, and a $1 billion round announced in May 2026 put its valuation at $22 billion.

Both platforms sell contracts that pay $1 if an event happens and $0 if it doesn't. Each held about half of their combined volume in March 2026, according to Pew Research Center. For the 30 days to October 7, DeFi Rate data put Kalshi's share of tracked volume at 75.6%, compared with 11.6% for Polymarket US and 5.3% for the international site.

Here is a quick side-by-side comparison of both platforms:

What Changed for Polymarket and Kalshi in 2026

Six changes this year have made earlier descriptions of both platforms inaccurate.

• Polymarket now charges fees: Trading on the international site was free in 2025. Most categories have charged for market orders since March 30, 2026. Only geopolitical markets remain free.
• A new settlement token: Deposits now convert automatically into pUSD, Polymarket's own dollar token on Polygon. It replaced bridged USDC on April 28.
• US residents can use Polymarket again: On May 12, Polymarket US removed its waiting list for iPhone users. US residents remain blocked from the international site.
• Both platforms added perpetual futures: Kalshi listed a Bitcoin contract for US users on June 3. International users gained access to Polymarket's version on September 3.
• US courts disagree on state gambling law: After one federal appeals court sided with Kalshi in April, two others ruled for state regulators in August and September. The Supreme Court has been asked to settle the disagreement.
• Sports bets drive most volume: Most trading on Kalshi and Polymarket US comes from sports contracts and multi-event combos. Politics accounts for only a small share of the sector.

Polymarket vs Kalshi: Products

Both platforms now offer leveraged futures alongside yes-or-no contracts covering sports, politics, the economy, crypto prices, and culture. Kalshi keeps these products in one regulated account, while Polymarket separates them across two platforms with different rules.

Polymarket Products

Accounts and balances are separate on the international site and US app. Product access depends on the user's country.

1. International event markets: Outcome shares trade through an order book and settle on Polygon. For the pricing model, see our guide to how prediction markets work.
2. Polymarket US: Sports accounted for 98.4% of the app's volume in the 30 days to October 7. Its contracts also cover politics, crypto, weather, and economics, all in US dollars. The app is available on iPhone, with no Android version yet.
3. pUSD balance: All international trades use pUSD. USDC backs it one-to-one, and smart contracts enforce that backing.
4. Combos: Both Polymarket platforms offer combos, which join several sports outcomes into one position. It pays only if every part is correct.
5. Short crypto markets: Contracts on whether a coin will rise or fall settle every 5 or 15 minutes. Settlement uses prices from the Chainlink data network.
6. Perpetual futures: Using pUSD as collateral, international users can trade leveraged contracts on crypto, stock indices, oil, gold, and silver.
7. Rewards: Traders with resting orders receive a share of the fees paid in their market. Positions in 18 selected long-term markets earn 3.25% a year.
8. Data and partners: Dow Jones publications and Intercontinental Exchange, Polymarket's largest shareholder, receive its price data. Major League Baseball and the National Hockey League are among its sports partners.

Kalshi Products

Kalshi combines event contracts and futures in one US dollar account, with interest on cash.

1. Event contracts: Every contract is listed under CFTC rules and settles in dollars. Markets cover sports, elections, inflation, interest rates, weather, and crypto prices.
2. Combos: Kalshi's largest product, multi-event positions, made up 64.3% of its volume in the week ending October 4. Single sports contracts accounted for about 19.8%.
3. Perpetual futures: Kalshi's 20 contracts cover 18 crypto assets plus gold and silver. Our explainer on Kalshi perpetuals describes margin and funding.
4. Interest on balances: US users with at least $250 earn a variable 3.50% a year on cash and open positions. Interest is paid monthly.
5. Kalshi Prime: This affiliated brokerage launched in June 2026 for professional trading firms. It is registered as a futures commission merchant, the US license for handling customer derivatives accounts.
6. Partner apps: Robinhood and Coinbase list Kalshi markets in their apps. Robinhood agreed in September 2026 to send orders to a rival exchange too.
7. Tokenized contracts: Thousands of Kalshi markets have also traded as tokens on the Solana blockchain since December 2025.
8. News data: CNBC, The Associated Press, and CBS News use Kalshi prices in reporting, including their coverage of the 2026 midterm elections.

Polymarket vs Kalshi: Fees

Fees on both platforms equal a fixed rate multiplied by the number of contracts, the price, and one minus the price. They peak at 50 cents and approach zero as the price nears $0 or $1. Market orders pay taker fees, while limit orders that rest in the order book are maker orders. Our page on maker and taker fees explains the distinction.

Trading Fees

• Polymarket international: Geopolitical markets are free, and makers never pay. For market orders, the official fee table sets a rate of 0.07 for crypto and 0.05 for sports, economics, culture, and weather. Politics, finance, and technology markets use 0.04.
• Polymarket US: Every category has used one rate of 0.0695 since October 1, 2026. Makers receive rebates of up to $0.31 per 100 contracts.
• Kalshi: The fee schedule effective July 7, 2026 sets the taker rate at 0.07. Maker orders are free on most markets, but a listed group that includes major sports series charges makers at 0.0175. Combos charge double.

Fee example: On Kalshi, buying 100 contracts at 50 cents costs $50 plus a $1.75 fee, equal to 3.5% of the amount paid. For the same order in a politics market, Polymarket's fee is $1.00, or 2%. Resting limit orders are free on Polymarket and most Kalshi markets.

Deposits, Withdrawals, and Interest

• Polymarket international: Deposits are accepted from 15 blockchain networks. Minimums are $2 on most networks and $7 on Ethereum. Polymarket charges no deposit or withdrawal fee, although card providers such as MoonPay set their own fees.
• Polymarket US: The app accepts debit cards, bank transfers, Apple Pay, PayPal, Venmo, and wires. Withdrawals return to the original payment source and are free.
• Kalshi: Bank deposits and withdrawals are free, with deposits capped at $10,000 each. Debit card deposits cost up to 2%, and withdrawals to a debit card cost $2. Deposits in USDC, BTC, SOL, XRP, and two other crypto assets convert to dollars.
• Interest: Kalshi's 3.50% applies to the whole account. Polymarket's 3.25% is limited to positions in selected markets, with no interest on idle cash.

Market orders cost less on Polymarket in most categories. Traders who fund their accounts from a bank and hold cash between trades pay less on Kalshi.

Polymarket vs Kalshi: Markets and Liquidity

Kalshi is several times larger than the two Polymarket platforms combined. Large orders move prices less in markets with more resting orders, so size matters most for these trades. Our prediction market statistics page tracks the sector over time.

Volume and Open Interest

• Kalshi: Open interest, the value of contracts not yet settled, stood at $2.5 billion on October 7. September 2026 was its largest month, with $60.7 billion in trading.
• Polymarket: September's $8.8 billion was a record for the US app. The international site traded $4.5 billion in the 30 days to October 7 and held $339 million in open interest.
• How volume is counted: Data providers count each contract at its $1 payout value. The amount paid is much lower: across all tracked platforms, $89.4 billion of reported volume represented $23.4 billion paid.

Market Categories

• Sports: On the international Polymarket site, sports represented 46.2% of recent activity. Sports contracts and combos account for most Kalshi volume and nearly all Polymarket US volume.
• Politics: Pew counted $1.3 billion in Polymarket political volume in June 2026, against $261 million on Kalshi. Polymarket's political markets are much deeper.
• Crypto: In the latest 30-day period, price markets made up 16.8% of international Polymarket volume and 14.4% of Kalshi volume.

How Markets Are Resolved

• Polymarket international: Most markets settle through the UMA oracle. Under this system, anyone can post a bond to propose a result. Disputed results go to a vote of UMA token holders, a process that can take four to six days.
• Polymarket US and Kalshi: The exchange decides results using the sources named in each contract's rules. Its decisions are final.
• Disputes: Traders filed a $54 million class action against Kalshi in March 2026 after it applied a death exception to a market on Iran's supreme leader. Polymarket has faced several contested oracle votes. Rule wording has caused losses on both platforms.

Prices broadly match real outcomes, according to a study of more than 300,000 Kalshi contracts. Cheap contracts, though, win less often than their prices suggest. Average losses were almost 32% for traders using market orders and about 10% for makers.

Polymarket vs Kalshi: Perpetual Futures

Perpetual futures follow an asset's price and allow leveraged positions without an expiry date. An event contract has a fixed stake, but the platform can close a leveraged position if the price moves against it.

• Kalshi: The CFTC approved the Bitcoin contract on May 29, 2026, and trading began on June 3. Only US users can trade Kalshi perpetuals. Its perpetuals page lists leverage of 5.8x on Bitcoin, 4.4x on Ethereum, and 15.2x on gold.
• Polymarket: The product launched on September 3, 2026, and is blocked for residents of the United States and Canada. Leverage reaches 20x on crypto, the S&P 500, oil, gold, and silver. Other assets have a 10x limit.
• Fees: A $10,000 market order costs $12 on Kalshi and $4 on Polymarket. Kalshi's entry-level rates are 0.12% for takers and 0.05% for makers. Polymarket's schedule starts at 0.04% for takers and 0.0125% for makers.
• Funding: Every eight hours, holders of Kalshi crypto contracts pay or receive funding. Our funding rates tracker shows current market levels.

Polymarket combines higher leverage with lower fees but excludes US users. Kalshi offers lower leverage within a US-regulated exchange. For more contract choice, see our crypto futures exchange comparison.

Polymarket vs Kalshi: Security

Users can lose funds to hacks or stolen logins. Prices pose a separate risk when people with private information about an event distort them.

Polymarket Security Measures and History

• Wallet model: International balances are held on Polygon in a wallet linked to the user's login, which the user must protect. Polymarket US holds dollars in a regulated clearinghouse.
• December 2025: A vulnerability at an outside login provider let attackers empty a small number of accounts.
• May 2026: Attackers stole more than $520,000 after the private key of a company wallet used to pay rewards was exposed. Polymarket said user funds were safe.
• June 2026: Polymarket promised full refunds after malicious code inserted through a website supplier drained about $3 million from more than 11 users.
• Insider trading: US prosecutors charged an Army soldier in April 2026 with using classified information to earn about $410,000 on Polymarket.
• Regulator inquiry: The CFTC opened an investigation after criminals attempted to steal at least $10 million through Polymarket US in February 2026.
• New controls: US users gained self-exclusion periods and deposit limits through a safety program launched on September 30.

Kalshi Security Measures and History

• Custody: Every user completes an identity check before trading. Customer dollars are held through Kalshi Klear, a clearinghouse registered with the CFTC.
• Incident record: Some deposits were delayed during the Super Bowl in February 2026, but we found no public report of customer funds lost to a hack.
• Insider trading cases: A CFTC enforcement notice describes a political candidate who traded on his own race and a video editor who traded on unpublished content. Kalshi has fined and suspended several users.
• Volume questions: In September 2026, an analyst reported that trading in Kalshi's Ethereum futures was very high compared with the value of open positions. Kalshi denied that the trades were artificial.
• Surveillance: In August 2026, Kalshi signed a multi-year agreement to monitor its markets with Nasdaq surveillance technology.

Kalshi has the cleaner record on customer funds. International Polymarket users control their balances directly, reducing some company risk but taking on wallet risk. Keep balances limited to what you need for open trades, and move other crypto to a self-custody wallet.

Polymarket vs Kalshi: Regulation and Country Access

The legal gap is smaller than older articles suggest because both companies hold CFTC exchange licenses. Whether US states can apply gambling laws to sports contracts on federally regulated exchanges remains unresolved.

Polymarket Licenses

• 2022 settlement: Polymarket paid a $1.4 million penalty to the CFTC for offering unregistered contracts, then blocked US users from its site.
• US license: In 2025, Polymarket paid $112 million for the licensed exchange QCEX. The CFTC approved an amended license that November, also permitting access through brokers.
• State action: In May 2026, a Nevada court granted an injunction against Polymarket. New York's attorney general sued on September 24, alleging unlicensed gambling. Polymarket countersued in federal court.
• International restrictions: The official restriction list blocks new positions from Australia, Belgium, Brazil, France, Germany, Italy, Poland, Singapore, Taiwan, Thailand, the United Kingdom, and four Canadian provinces. Our Polymarket restricted countries page lists every market.
• Identity checks: Most international accounts need only a wallet or email login. Polymarket US requires a Social Security number, date of birth, and address.

Kalshi Licenses

• Federal status: Kalshi operates an affiliated brokerage alongside its CFTC-designated exchange and registered clearinghouse.
• Appeals courts: In April 2026, the Third Circuit ruled that federal law overrides New Jersey's gambling rules for Kalshi's sports contracts. In August, the Ninth Circuit and in September, the Sixth Circuit, ruled the other way for Nevada, Ohio, and Tennessee.
• Supreme Court: New Jersey officials filed a petition in September asking the court to settle the conflict. A brief from 39 states and the District of Columbia supports the petition. Kalshi must respond by November 9, 2026.
• State restrictions: A court order in Michigan blocks sports contracts. In Nevada, Kalshi agreed in July to stop offering event contracts. A Washington court barred sports and election markets in August.
• New York: After the state's July 2026 lawsuit sought a nationwide halt, the CFTC issued an emergency order on August 11 telling Kalshi to keep operating.
• International access: Kalshi opened to more than 140 countries in late 2025. Its member agreement bars event contract trading from the United Kingdom, Canada, Australia, France, India, Singapore, and 49 other jurisdictions.

Kalshi's website and apps for both iPhone and Android give it the win on US access. Polymarket US works only on iPhone. Pending CFTC rules on event contracts could change access on both platforms.

Opening a Polymarket account is easier outside the US, where most international accounts need no identity check, and crypto deposits start at $2. Its help page lists 39 blocked countries. Kalshi excludes 55 jurisdictions and verifies every user.

Is Polymarket Better Than Kalshi?

Polymarket is the better platform for most traders. Makers pay no fees, and market orders cost less in every category except crypto, where they match Kalshi's. International users can open an account with a wallet and a $2 deposit. Its political markets also draw several times more trading than Kalshi's.

Kalshi is the better choice for US residents who want a website, an Android app, free bank transfers, and interest on cash. Its higher open interest benefits large sports orders, and it has no reported hack of customer funds. Readers who choose Polymarket can start with our list of Polymarket trading strategies.

Final Thoughts

Sports combos lifted Kalshi's volume far above Polymarket's as it spent 2026 turning a prediction market into a wider derivatives exchange. That growth rests on a legal argument rejected by two appeals courts. A Supreme Court decision could confirm its national reach or leave sports contracts to individual states.

Within nine months, Polymarket introduced fees and a new settlement token, added a US exchange, and launched leveraged futures. Security failures and a regulator inquiry accompanied that expansion. Our list of decentralized prediction markets covers other onchain options.

Check that your country or state is supported before depositing on either platform, and read each market's full rules. Use limit orders where possible to avoid most fees. Since an event contract can fall to zero, trade only with money you can afford to lose. Nothing on this page is financial advice.