Kalshi vs Polymarket (2026): Fees, Liquidity, State Limits and Verdict

Kalshi and Polymarket are the two best-known prediction markets, but for a US resident the choice is narrower than it looks. Americans cannot open new trades on Polymarket's global site. They use Polymarket US, a separate app on its own CFTC-regulated exchange, with its own fees, catalog and state list. This page compares Kalshi with that US app. All facts are as of October 2026 and linked to their sources.

Our ratings: Kalshi 4.6 / 5, Polymarket 4.5 / 5 (how we rate). We earn a commission on Polymarket sign-ups and nothing from Kalshi.

Verdict: which one to pick

• Pick Kalshi if you live in Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada or Ohio. Polymarket US is not available in those eight states. Kalshi has its own limits in Nevada and Michigan, covered below.
• Pick Kalshi for depth and breadth. It carried about 76% of tracked prediction-market volume in the month to October 15, 2026, against about 12% for Polymarket US. It lists more categories, has a full web platform and pays 3.50% variable interest on balances of $250 or more.
• Pick Polymarket US if you post limit orders and your state is served. Taker fees are now almost the same on both, $1.74 against $1.75 per 100 contracts at 50¢, but Polymarket US pays makers a rebate.
• Use both if you compare prices. The same event often trades at different prices on the two exchanges, and the cheaper side changes from day to day.
• Already on Robinhood? Its event contracts route partly to Kalshi; see the Robinhood review.

At a glance

Sources for each row are linked in the sections below.

Regulation and history

Kalshi

Kalshi was founded in 2018 and designated a contract market by the CFTC in November 2020, the first exchange approved specifically for event contracts. It opened to the public in 2021. A federal district court ruled for Kalshi on election contracts in September 2024, and the CFTC dropped its appeal in May 2025 (Covers). Its later move into sports brought the state lawsuits described under state availability.

Polymarket

Polymarket launched in 2020 as a crypto-based market on the Polygon blockchain, settled in USDC. In January 2022 it paid a $1.4 million penalty to the CFTC for offering unregistered markets and blocked US users from its main site.

The US return came in three steps:

1. July 2025. After the CFTC and Justice Department closed their investigations, Polymarket bought QCX LLC and QC Clearing LLC, a CFTC-licensed exchange and clearinghouse, for $112 million (Covers).
2. November 2025. The CFTC issued an amended order of designation, signed November 24 and announced November 25, letting the exchange onboard US customers and brokers directly (same source).
3. 2026. The US app opened in stages. Political and economic markets arrived in April (DeFi Rate), and the iOS waitlist ended on May 12 (Covers).

The global site still exists and still settles in USDC, but it is not open to new trades from US residents. Everything else on this page refers to Polymarket US unless it says otherwise.

What CFTC regulation means

Both exchanges must keep customer money apart from company money, watch for manipulation and keep audit trails. Neither offers margin, so you cannot lose more than you pay for a position. A balance on either is not FDIC- or SIPC-insured. Federal regulation also does not settle whether states can treat sports contracts as gambling. That question is now before the courts, and it affects Kalshi far more than Polymarket US so far, because Kalshi offers sports in more states.

Fees

Both exchanges charge takers (orders that fill immediately) a fee that depends on the contract price. Both use the same shape of formula, with a different multiplier.

Here p is the price in dollars. Fees peak at 50¢ and fall toward zero near 1¢ or 99¢.

Taker fees on 100 contracts

The peak Kalshi fee is $1.75 per 100 contracts, which is $50 of capital. Putting $100 into 50¢ contracts means 200 contracts and about $3.50 in fees on Kalshi, or $3.48 on Polymarket US. Some Kalshi series use other rates; the order ticket shows the exact fee.

Maker orders and rebates

• Kalshi: resting limit orders pay nothing on most markets, though some series charge makers a fee.
• Polymarket US: makers earn a rebate of 0.0125 × contracts × p × (1 − p), about 31¢ per 100 contracts at 50¢. Large takers also get rebates based on monthly volume. From October 19, 2026 both maker and taker rebates move to new volume tiers, and accounts under $10 million a month in maker volume get no maker rebate (Polymarket US fee schedule, October 2026).

Funding fees

Kalshi charges nothing for bank transfers and up to 2% on debit-card deposits (Kalshi help center). Finder reports that Polymarket US charges no deposit fee and says withdrawals are free (Finder, October 16, 2026). Your bank may charge for wires on either.

Which is cheaper

For takers, neither. Since Polymarket US raised its rate to 0.0695 in October 2026, the two fees are within a cent or two at every price: $1.74 against $1.75 per 100 contracts at 50¢, and $0.63 on both at 10¢ and 90¢. The differences that matter are elsewhere. Polymarket US pays makers a rebate, and Kalshi pays interest on balances of $250 or more.

Interest on cash

Kalshi pays interest on both uninvested cash and money in open positions. Its help center says the rate "is set at 3.50%", is variable, is paid only on balances of $250 or more, and needs an SSN for payments above $10 a year (Kalshi help center, October 2026). A steady $5,000 balance earns about $175 a year at that rate.

Polymarket US does not advertise interest on balances. Neither balance is a bank deposit, so treat the interest as a small offset to fees, not a savings account.

Liquidity and volume

DeFi Rate's tracker splits volume across the venues it follows. For September 16 to October 15, 2026 (DeFi Rate, updated October 16):

Polymarket's international exchange traded about $4.7 billion in September 2026 at face value, but US residents cannot trade on it. Older claims on this site that Polymarket was the largest market at "$9B a month" are out of date, and so is an open-interest figure attributed to Binance Research, which we could not trace and have removed.

For US traders this means Kalshi's books are usually deeper, especially on sports and economic data. On the most popular contracts both exchanges are liquid enough for trades of a few hundred dollars. Differences show up in large orders, niche contracts and the last minutes before a market closes.

Markets

Both list binary Yes/No contracts that settle at $1 or $0. Both also group related contracts into one event, so a question such as "Who wins the 2028 nomination?" appears as one page with a row per candidate.

Kalshi lists hundreds of markets across economics (CPI, jobs, GDP, Fed decisions), politics (Congress, governors, approval ratings), sports, weather (city temperature highs, hurricanes), financial indexes and crypto prices, culture and company events. See the Kalshi review and our 2026 midterm tracker.

Polymarket US lists contracts in seven categories: sports, politics, crypto, economics, weather, tech and culture (Finder, October 2026). It started with sports and added politics and economics in April 2026. The catalog is smaller than Polymarket's global site, which lists thousands of markets on world politics and current events that US residents cannot trade.

For US economic releases and US sports, Kalshi has the larger menu. For Polymarket's trademark world-news markets, check whether the US app carries the contract before you open an account for it.

Deposits and withdrawals

Sources: Kalshi transfers FAQ and Finder's Polymarket review, both October 2026. Finder reports Polymarket US caps debit-card and ACH deposits at $50,000 a day.

On Kalshi, part of a bank deposit is often available right away and the rest settles within about five business days. Recently deposited bank funds can be held briefly before you can withdraw them. Linking a checking account and using ACH is the cheapest route on both.

State availability

This changes faster than anything else on this page. Check each app before you fund it.

Polymarket US

Not available in Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada and Ohio (OddsShopper, as of August 18, 2026). A Minnesota law that would have banned prediction-market platforms was blocked by a federal court on July 27, 2026, so the app remains available there for now.

Kalshi

Kalshi has no state where the whole platform is closed, but several states have removed categories or are in court. As of October 15, 2026 (OddsShopper):

Quick lookup

State guides: California, Texas, Florida, New York, New Jersey, Illinois, Massachusetts and Nevada.

Apps

Kalshi runs iOS, Android and web versions with the same markets. The iOS app is rated 4.8 out of 5 from about 604,000 ratings (App Store, October 2026). It reads like a brokerage app: each market shows a chart, the order book and the full rules. Support runs through the help center and email, and slow replies during busy events are a common complaint.

Polymarket US opened to all US iPhone users on May 12, 2026. Finder shows ratings of 4.5 on the App Store and 3.5 on Google Play as of October 2026. Reports conflict on whether the US Android app and a web version are open to everyone, so check polymarket.com for your device. The design carries over from the global site: dense market cards, live prices and a comment thread under each market.

If you trade from a desktop, Kalshi is the safer choice today.

Welcome offers

Kalshi offers change with the code used. In October 2026, published codes gave trading credit after a qualifying first trade, with Nevada and Washington usually excluded (Covers, October 9, 2026). Credit is for trading. Profits from it can be withdrawn; the credit itself cannot. Our Kalshi promo code guide has the details.

Polymarket US offers also change. We do not quote an amount because none is fixed. If you sign up through our Polymarket link we earn a commission, which does not change the offer you see. See the Polymarket promo code guide.

Neither offer should decide the choice. Fees, state access and the markets you want matter more over a year of trading.

Sports contracts

Both exchanges list game outcomes for the NFL, NBA, MLB, college sports and soccer. Kalshi has the larger sports book in the US by volume and lists more leagues and contract types. It also carries most of the legal risk: Nevada, Michigan and Washington users have lost sports boards, and Ohio's may follow.

Polymarket US started as a sports app and is available in fewer states. Where both are open, compare prices before each trade; the difference after fees is often a cent or two per contract. For more options, see best platforms for sports event contracts.

Trading the price gap between them

When the same event trades at different prices on the two exchanges, you can sometimes lock in a small profit by buying opposite sides. An example with real fee formulas:

• Kalshi: Candidate A Yes at 55¢, so No costs about 45¢.
• Polymarket US: Candidate A Yes at 51¢.
• Buy 100 Yes on Polymarket US for $51.00 and 100 No on Kalshi for $45.00. One side pays $100 whatever happens.
• Gross profit: $4.00. Fees: $1.74 on Polymarket US and $1.74 on Kalshi. Net: about $0.52 per 100 contracts.

Fees take most of a 4¢ gap. The other risks:

1. Different rules. The two contracts may settle on different sources or dates, or treat edge cases differently. Read both rulebooks. If they settle differently, you can lose on both sides.
2. Capital tied up. Your money sits on two exchanges until the event resolves, often for months, earning interest only on the Kalshi side.
3. Depth. A gap on screen may vanish after the first few hundred contracts.
4. State access. You need both apps open to you, which rules out the eight states where Polymarket US is unavailable.

Price-tracking tools exist for this. One is KalshiSpy, a paid third-party tool that shows what top Kalshi traders are buying. It is not part of Kalshi, and we earn a commission on subscriptions. Try KalshiSpy (paid third-party tool, affiliate link) →

Who should use which

Kalshi suits you if:

• You live in one of the eight states Polymarket US does not serve, outside the categories Kalshi has closed there.
• You trade US economic data, US politics or US sports and want the deepest books.
• You keep $250 or more on the exchange between trades and want the interest.
• You trade from a computer.

Polymarket US suits you if:

• Your state is served and you trade mostly with limit orders, so the maker rebate adds up.
• You place limit orders and want to earn maker rebates.
• You want Polymarket's style of markets and comment threads in a regulated US app.

Many active traders hold both and use whichever has the better price.

Visit kalshi.com → · Open a Polymarket account (affiliate link) →

Frequently asked questions

Is Kalshi or Polymarket bigger?

Kalshi, for US traders. It had about 76% of tracked prediction-market volume between September 16 and October 15, 2026, against about 12% for Polymarket US and 5% for Polymarket's international exchange, per DeFi Rate.

Can Americans use Polymarket?

Yes, through Polymarket US, a separate CFTC-regulated app. It is not available in Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada or Ohio. US residents cannot open new trades on Polymarket's global site.

Which has lower fees?

For takers they are now almost the same. Polymarket US charges 0.0695 × contracts × p × (1 − p) as of October 2026, up from 0.06 when its fee started on July 1. Kalshi's general rate is 0.07. At 50¢ that is $1.74 against $1.75 per 100 contracts. Polymarket US pays makers a rebate; Kalshi charges makers nothing on most markets.

When did Polymarket become legal in the US?

Polymarket bought the CFTC-licensed exchange QCX in July 2025. The CFTC's amended order, signed November 24 and announced November 25, 2025, let it onboard US customers directly. The iOS app opened to all US users on May 12, 2026.

Does Kalshi still pay interest?

Yes. As of October 2026, 3.50% APY, variable, on balances of $250 or more, including money in open positions. Interest above $10 a year needs an SSN on file.

Is Kalshi available in every state?

The platform is, but not every category. Nevada users cannot trade sports, entertainment or election contracts; Michigan's sports boards are dark; a Washington court order blocks sports, election and several other categories. Ohio and Tennessee may follow after a September 2026 appeals ruling.

Can I profit from price differences between Kalshi and Polymarket?

Sometimes, but fees take most of the gap. A 4¢ gap on 100 contracts at around 50¢ leaves about 52¢ after both fees. Different settlement rules can turn a hedge into a loss on both sides.

Which is better for beginners?

Kalshi, for most people. It is available in more states, has a web platform, accepts more payment methods and has deeper books. Polymarket US is a fair choice for beginners in states it serves who mainly want sports or Polymarket's style of markets.

Sources

• Kalshi: fee schedule, APY on Kalshi, transfers FAQ, card deposits (checked October 2026); Kalshi on the App Store (October 2026)
• Polymarket US fee schedule (October 2026)
• OddsShopper: Polymarket fees and blocked states (September 2026)
• OddsShopper: where Kalshi is legal (October 15, 2026)
• DeFi Rate volume tracker (October 16, 2026); DeFi Rate on Polymarket US politics launch (April 2026)
• Finder: Polymarket review (October 16, 2026)
• Covers: CFTC amended order for Polymarket (November 2025), Polymarket iOS launch (May 2026), CFTC drops Kalshi appeal (May 2025), Kalshi promo codes (October 9, 2026)