Kalshi vs Polymarket: how the two largest prediction markets compare in 2026

Kalshi and Polymarket are the world's largest prediction market platforms. On both, traders buy and sell contracts tied to the outcome of real-world events. Each contract is priced between $0.01 and $0.99 and pays out $1.00 if the outcome you picked happens, or nothing if it doesn't, so the price works as the market's estimate of how likely that outcome is (a 60-cent contract implies a 60% chance). Polymarket launched in 2020, and Kalshi opened to the public in 2021 after receiving its federal license in 2020. Both cover thousands of events across sports, politics, crypto, culture, and finance, and both use a central limit order book (CLOB), a live list of buy and sell orders the exchange matches automatically, the same way a stock exchange works.

The commonalities end there. Kalshi is fully regulated by the Commodity Futures Trading Commission (CFTC), the US agency that oversees futures and derivatives markets, and it settles trades in regular US dollars like a traditional exchange. Polymarket settles trades in USDC, a stablecoin, meaning a digital dollar that always aims to be worth $1. In the Polygon blockchain. It runs two versions: a CFTC-regulated US platform (Polymarket US) and a larger international one (Polymarket International) that operates separately. The two platforms charge different fees, dominate different categories—Kalshi has historically leaned towards sports trading, while Polymarket leads in politics and world events—and aren't equally accessible in every territory or US state.

Combined monthly prediction market volume across the two platforms reached $44.8 billion in June 2026, according to The Block, more than triple the ~$14 billion average monthly handle of all legal US sports books in 2025, per a Pew Research Center analysis.

Disclaimer: This guide is for educational purposes only. It is not financial advice, not a solicitation, and not for UK audiences. Prediction market event contracts are risky and not suitable for all users.

When to use Kalshi vs Polymarket

The right prediction market platform depends on what someone wants to trade, where they're located, and how they prefer to fund an account. There's no single best answer. Neither platform cancels out the other, many active traders keep accounts on both Kalshi and Polymarket, depending on which one has the better prices and more liquidity or volume for a given market.

How Kalshi and Polymarket trades are structured differently

The practical difference between Kalshi and Polymarket for traders: Kalshi runs a traditional centralized exchange you fund with regular money, ACH bank transfer, wire, debit card, PayPal, Venmo, or Google Pay. Polymarket International runs on the blockchain, so you fund it with USDC or with any EVM token on a supported network using a leading crypto wallet like MetaMask. Polymarket US is a separate regulated version with its own rules. That split shapes everything from how fees work to how fast money moves in and out, which is what the rest of this comparison digs into.

Kalshi vs Polymarket trading volume in 2026

Kalshi and Polymarket count volume differently. Kalshi reports what's called notional volume: every contract counted at its $1 face value, regardless of the price actually paid. Because a contract that trades at 30 cents still adds $1 to the notional tally, that figure can look larger than the cash actually changing hands. Polymarket's reported figures are compiled on a different basis. Analysts who track both platforms caution that the two aren't measured identically, so the numbers below are best read as a guide to scale rather than a precise apples-to-apples comparison.

Table sources: The Block (volume figures) · Kalshi $22B Series F + revenue · ICE $2B Polymarket investment

Does Kalshi or Polymarket have more sports and politics volume?

The two platforms have ended up specializing in different things, and the split is sharper than most people realize. (For a broader survey of what categories prediction markets cover, see the guide to the top prediction market categories in 2026.)

A Pew Research Center analysis published May 27, 2026 found that since July 2024, sports has accounted for 80% of total trading volume on Kalshi and 39% on Polymarket. Sports, politics, and crypto combined make up 91% of Kalshi's volume and 90% of Polymarket's over the same period.

Kalshi's sports dominance has been its primary growth engine—that single category is the platform's core money-maker. Polymarket's politics dominance tells the opposite story: politics and world events are where it pulls away, its 2024 US election markets traded billions of dollars in volume, and it remains the deepest pool for political event contracts anywhere. It also keeps trading free on all geopolitical and world-events markets, which pulls activity into categories where Kalshi charges standard fees. And because most of its users already hold crypto, Polymarket sees heavy trading in markets that bet on cryptocurrency prices, too.

The 2026 FIFA World Cup pushed this further. On Kalshi, the World Cup Winner market had reportedly drawn more than $800 million in bets by early July 2026. But that single headline market only scratches the surface—both platforms list hundreds of World Cup contracts, from three-way match outcomes to Golden Boot player props. On Polymarket, the World Cup Winner market—the largest sports market in the platform's history—had taken in about $3.9 billion by July 7, 2026, crossing $4 billion the following day.

What contracts can you trade on Kalshi vs Polymarket?

Both platforms trade binary event contracts, but what's available, how markets get listed, and how they resolve all differ. On Kalshi, every market goes through formal approval, which limits how many there are but adds a layer of regulatory review. Polymarket lets anyone create a market on almost any topic—which is how it ends up with the niche and viral markets you won't find on Kalshi.

In mid-2026, Kalshi also launched perpetual futures on crypto—a type of contract that lets you bet on the movements of a token's price with no expiry date, starting at zero fees to build up trading activity. The Bitcoin perpetual future went live first on June 3, 2026, with Ethereum and XRP contracts following shortly after and Solana announced to come.

Parlays, single bets that combine several outcomes, where all of them have to hit for the bet to win, have become a big driver in 2026. Since the 2026 FIFA World Cup opened on June 11, parlays have made up almost half of Kalshi's total volume, according to InGame's analysis of Kalshi data. Polymarket offers parlays too, though they make up a smaller share of its activity.

If you already hold crypto, Polymarket has an edge on convenience: because it runs on the blockchain, you can fund trades straight from a self-custodial wallet, a crypto wallet where you, not a company, control the funds. MetaMask prediction markets, powered by Polymarket, are available to trade live in two taps from a mobile device.

Kalshi fees vs Polymarket fees

Both platforms charge fees that scale with how uncertain a market is: more on coin-flip (close to 50/50) contracts, less on near-sure things. And both split traders into two groups. Takers buy or sell instantly by grabbing an order that's already sitting there; they pay the main fee. Makers post an order and wait for someone else to take it; they pay little or nothing, because they're adding options for everyone else to trade against. The basic idea is the same on both platforms, but the rates aren't.

Kalshi uses one formula for most markets: the fee is highest on the most uncertain bets and shrinks as an outcome becomes more certain. At the most uncertain point (a contract priced around 50 cents), the taker fee peaks at 1.75 cents per contract. Makers pay about a quarter of that. Funding by bank transfer (ACH) or wire is free; debit cards cost 2%. There's no fee to cash out. (The exact formula: 0.07 × price × (1 − price) per contract, rounded up to the nearest cent.)

Polymarket started charging taker fees on March 30, 2026, and the rate depends on the category. At the most uncertain price point, fees run from $0.75 per 100 shares on sports up to $1.75 on crypto, with politics, finance, and tech in between. Geopolitics and world events stay completely free. Makers pay nothing—and better yet, they earn a daily rebate (a partial refund) paid out of the fees takers pay. There are no fees to deposit, withdraw, or cash out on Polymarket itself, though you'll still pay small blockchain network fees, plus a card-processing fee if you buy USDC with a card through a third-party provider such as MoonPay.

Table sources: Kalshi fee schedule (PDF) · Polymarket fee documentation

What this means in practice: Polymarket's zero maker fees and rebates can reduce costs, especially for high volume traders. Kalshi's bank funding and automatic 1099 tax forms are designed to simplify trading, however users typically pay more per trade in the middle price range (30–70 cents). (Fees are only half the cost of a trade; the gap between buy and sell prices is the other half, and it adds up fast on quieter markets.)

That fee gap shows up in revenue. InGame's analysis of Kalshi trade data found Kalshi has generated about $1.15 billion in total fee revenue since launch, with roughly $850 million of that coming in 2026 alone, and sports contracts driving the bulk of it. During the World Cup, Kalshi's daily fees topped $13 million on peak days. Polymarket, which only switched on taker fees in March 2026, earns far less by comparison.

Kalshi vs Polymarket regulatory issues

Kalshi received its CFTC designation as a contract market in 2020, the first federally regulated event contract exchange in the US, and opened to the public in 2021. A designated contract market (DCM) is the same official license the CFTC gives to major futures exchanges. Kalshi started with markets on economic data, weather, and politics before adding sports contracts in January 2025.

Polymarket also launched in 2020, as a blockchain-based prediction market settling trades in USDC on the Polygon network. In July 2025, Polymarket acquired two CFTC-licensed companies, the QCX exchange and QC Clearing clearinghouse, for $112 million, rebranding them as Polymarket US and Polymarket Clearing. That September, Polymarket received a no-action letter from the CFTC, signaling that regulators wouldn't take further enforcement action against the platform. In November 2025, the CFTC granted an Amended Order of Designation, the formal approval that cleared Polymarket to offer intermediated US market access. By December 2025, Polymarket began rolling out its US app.

Are Polymarket and Kalshi legal in every US state?

Both platforms are available to US residents through their CFTC-regulated arms. Kalshi has held its license since 2020, and Polymarket US launched in December 2025 after buying the licenses it needed. But "available" and "accessible everywhere" aren't the same thing.

A growing number of states argue that sports-related event contracts are really just unlicensed gambling. As of early July 2026, officials in at least 11 states have sent formal warnings ordering prediction market companies to stop, and legal fights are underway in more than a dozen states, according to CBS Sports. The CFTC, under Chairman Michael Selig, has pushed back by suing several states, arguing that federal law gives it, not the state, the final say over these markets. More than half of US states already limit betting on elections in some form, per Pew Research Center.

The outcome of these cases could decide whether prediction markets run under one nationwide set of rules or a messy patchwork that changes state by state. For the Polymarket vs Kalshi comparison, here's the practical difference: both face the same state-level challenges on sports contracts, but Kalshi's longer history as a fully licensed exchange gives it a slight edge in the legal argument that federal rules should win. Polymarket, meanwhile, keeps far more markets accessible overall thanks to its international version, in April 2026, Polymarket International handled about $9 billion in trading versus $1.3 billion on the US version, per Crypto Briefing's analysis. Some US traders reach the international platform using a VPN, but doing so steps outside the regulated US system.

Either way, checking current state-level restrictions before trading is essential—especially for sports event contracts.

Which platform has deeper liquidity, Kalshi or Polymarket?

Liquidity is just how easily you can get in and out of a bet at a fair price. In a liquid market, there are plenty of buyers and sellers, so you can trade the amount you want without pushing the price around. A market can look great on paper and still be nearly untradeable if there's no one on the other side.

Kalshi's sports markets are among the most liquid on either platform. Sports is its highest-volume category by far, and during the 2026 World Cup, single match markets like Canada vs. Morocco pulled in over $48 million in Kalshi trading, according to The Block. Because you can fund a Kalshi account with regular money, it also draws a wider everyday audience—Kalshi accepts PayPal, Venmo, Google Pay, and debit cards on top of bank transfers, so you don't need any crypto experience to start. Polymarket, by contrast, is funded with USDC from a crypto wallet.

Polymarket's political and geopolitical markets usually have more buyers and sellers than the same markets on Kalshi. A March 2026 TRM Labs analysis found that most of Polymarket's activity comes from moderately active traders (11 to 1,000 trades), with a smaller group of high-volume traders placing over 10,000 trades each. Polymarket's daily rebate gives these frequent traders a real reason to keep posting orders, which is what keeps those markets liquid.

Spreads—the gap between the best buy price and the best sell price—tend to be tightest on a platform's busiest markets. High-activity events like major elections, World Cup matches, and popular crypto price bets usually attract enough buyers and sellers to keep spreads narrow, while quieter markets tend to have wider spreads that quietly eat into your returns. If you're trading Polymarket markets through MetaMask, you can check the live spread before you place a trade, which can be used for assessing whether a low liquidity or small volume market is appropriate.