Kalshi vs Polymarket: Which Prediction Market Should You Use? (2026)
Kalshi holds your funds. Polymarket does not. That is the decision, and everything else follows from it.
Disclosure: Nika builds an app in this category, and Nika’s prediction markets are powered by Polymarket. We are not neutral, so we compare Kalshi and Polymarket on the public record and say plainly where each one wins.
Kalshi and Polymarket are the two largest prediction markets in the world, and they are built on opposite foundations. Kalshi is a CFTC-regulated US exchange that holds your dollars for you. Polymarket is onchain and non-custodial, so your funds stay in a wallet whose keys you hold.
Neither is better outright. The right pick comes down to three questions: who should hold your money, where you live, and what you actually want to trade. Kalshi is strongest on US sports and dollar funding. Polymarket is strongest on breadth, with politics, crypto and world events carrying real volume alongside sports, and it now runs a CFTC-regulated US arm too.
Most comparisons stop at “one is regulated, one is crypto.” That has not been true since 2025. Both are CFTC-regulated in the United States today. What actually separates them is custody. Search it either way, kalshi vs polymarket or polymarket vs kalshi, and the answer lands in the same place.
The 30 second answer
- Regulation: Both are CFTC designated contract markets in the US. Kalshi since November 2020. Polymarket US since December 2025, through the exchange it acquired.
- Custody: Kalshi holds your funds in segregated US bank accounts. Polymarket never holds them. You can export your private key.
- Funding: Kalshi takes dollars from a bank or card. Polymarket runs on stablecoins, onchain.
- Size: Kalshi is bigger by volume, and that is mostly a sports story. Polymarket’s volume is spread far more evenly across categories.
- Fees: The two now use the same fee formula. Polymarket’s rate is lower in most categories, and its makers pay nothing.
Kalshi vs Polymarket at a glance
Kalshi is a CFTC-regulated US exchange that holds your dollars in segregated bank accounts. Polymarket is a non-custodial exchange on Polygon where you hold your own keys, and it also runs a CFTC-regulated US arm called Polymarket US.
| Kalshi | Polymarket | |
|---|---|---|
| Structure | CFTC designated contract market | Onchain exchange, plus a CFTC-regulated US arm |
| Custody | Custodial, segregated US bank accounts | Non-custodial, you hold the keys |
| Funding | USD: ACH, debit, wire, Apple Pay, Google Pay | pUSD, an ERC-20 backed 1:1 by USDC |
| Rails | US banking | Polygon |
| Resolution | Exchange rules, own clearinghouse | UMA optimistic oracle, onchain settlement |
| Trading fee | 0.07 coefficient across markets | 0 to 0.07 by category, geopolitics free |
| Maker fee | 25% of the taker fee | None |
| Strongest in | US sports, economics | Politics, crypto, world events, sports |
| US access | All 50 states, some markets restricted | Polymarket US, iOS first |
| Outside the US | No, US-verified accounts only | Yes in most places, blocked in 40+ countries |
| Tax paperwork | 1099-MISC at $600 or more | None issued, you self-report |
As of August 2026. Fees, availability and legal status in this category change month to month. Confirm current rules before funding anything.
Regulation and legal access
Both platforms are federally regulated in the United States. The difference is how they got there, and it is a timing story rather than a legitimacy story.
Kalshi went the slow route. The CFTC granted KalshiEX LLC an order of designation as a contract market in November 2020, which made it the first exchange purpose-built for event contracts to operate onshore from day one. Its affiliated clearinghouse, Kalshi Klear, was approved as a derivatives clearing organization in 2024, so Kalshi runs its own registered clearing.
Polymarket went the fast route, and paid for it. It started offshore, then bought its way onshore. In July 2025 it acquired QCEX, a CFTC-licensed exchange and clearinghouse, for $112 million. That entity became QCX LLC, doing business as Polymarket US, and it now operates as a designated contract market under the same federal framework Kalshi uses. Polymarket US opened on iOS in May 2026 when the waitlist came off. Android and web were still rolling out at the time of writing.
How is Kalshi legal but Polymarket is not?
Both are legal in the US. Kalshi is legal because it is a CFTC-regulated exchange, and Polymarket US is a CFTC-regulated exchange too, so US residents can lawfully use it. The idea that only one of them is legal is out of date, and it is the single most common mistake in this comparison. What is still pending is the other thing: Polymarket filed with the CFTC on 28 April 2026 seeking approval to let US users trade directly on its main international exchange, which is the deeper, broader book. That filing had not been decided when this was published.
Put simply: both companies are federally regulated in the US, and Polymarket runs two products where Kalshi runs one.
Is Kalshi just sports betting with a regulatory workaround?
No, though it is a fair question to ask, and it is the misconception that runs the other way. Kalshi is a federally regulated derivatives exchange. Its contracts are event contracts under the Commodity Exchange Act, it does not set a line or take the other side of your trade, and it settles through its own CFTC-registered clearinghouse. The question exists because sports is roughly 80% of Kalshi’s volume, and several states argue that a sports outcome is a wager whatever the federal label says. That argument is exactly what the courts are split on, which is the next section.
The state fight, which is genuinely unresolved
The federal picture is settled. The state picture is not, and it moved in both directions in 2026.
In April 2026 the Third Circuit held that the CFTC likely has exclusive jurisdiction over Kalshi’s sports event contracts, and that the Commodity Exchange Act preempts New Jersey’s gambling laws. That was the first federal appeals court to rule on the question, and it went Kalshi’s way.
Then in July 2026 a federal judge in the Southern District of New York ruled that the Commodity Exchange Act does not preempt New York’s gambling law, which is the opposite outcome to the Third Circuit’s New Jersey ruling. New York’s attorney general has filed a civil enforcement action against Kalshi seeking $36 billion. The CFTC has sued several states asserting federal preemption. Minnesota’s ban took effect on 1 August 2026.
Read that as one thing: this is heading to the Supreme Court, and until it gets there, availability in your state can change while you hold an open position. That risk applies to every venue in this category, not just one of them.
Where you can actually use each one
Kalshi is US only. Accounts are US-verified, so it is not reachable from outside the country at all. Inside the US it is available in all 50 states, though several states restrict specific market categories, sports most often.
Polymarket is reachable from most of the world, which is the opposite shape. It is blocked in 40 or more countries, with France and Belgium fully blocked and Ireland and Singapore in close-only mode where you can exit positions but not open new ones. Local law still applies wherever you are.
Taxes
Kalshi issues a 1099-MISC when your net payouts reach $600 or more in a year, and files it with the IRS. Polymarket issues no US tax forms, so you self-report from your own records.
Neither arrangement changes what you owe. The IRS has not issued guidance specific to event contracts, and no published ruling settles whether the income is gambling, capital gains, or Section 1256 property. If you trade at any size, that is a conversation with an accountant, not with a blog.
Funding, fees and usability
Kalshi funds with dollars from a bank or a card. Polymarket funds with stablecoins, onchain. And one of the two changed how it charges trading fees in 2026, which is where most comparison pages are now wrong.
Kalshi takes dollars. ACH transfers and wires are free, debit card and Apple Pay or Google Pay deposits carry a 2% charge, and wires need a $1,000 minimum. Money lands in a company account, held in segregated US bank accounts under CFTC rules.
Polymarket takes stablecoins. Since the V2 upgrade on 28 April 2026 the settlement asset is pUSD, an ERC-20 on Polygon backed 1:1 by USDC, which replaced the bridged USDC.e the platform used before. Polymarket charges nothing to deposit or withdraw, and it sponsors gas through a relayer, so you are not paying network fees per trade. Intermediaries like an exchange or an on-ramp may charge their own fees to get you into stablecoins in the first place.
The fee comparison almost nobody has updated
Polymarket charged no trading fee for years. That changed in 2026, and most of the comparison pages ranking for this question still say “Polymarket is free.” It is not, and the real picture is more interesting than that.
Both platforms now price trades with the same formula: a coefficient, multiplied by the number of contracts, multiplied by the price, multiplied by one minus the price. Fees peak at 50 cents, where uncertainty is highest, and shrink toward the extremes. Kalshi applies a 0.07 coefficient. Polymarket sets a coefficient per category.
Here is what that means on a real trade. One hundred contracts bought at 50 cents, which is the most expensive point on the curve:
| Market | Coefficient | Taker cost on 100 contracts at 50c |
|---|---|---|
| Kalshi, any category | 0.07 | $1.75 |
| Polymarket, crypto | 0.07 | $1.75 |
| Polymarket, sports | 0.05 | $1.25 |
| Polymarket, economics, culture, weather | 0.05 | $1.25 |
| Polymarket, politics, finance, tech | 0.04 | $1.00 |
| Polymarket, geopolitics | 0 | $0.00 |
Rates from each platform’s published fee schedule, August 2026. Both are taker rates at the peak of the fee curve. Kalshi’s maker fee is 25% of its taker fee. Polymarket does not charge makers at all.
Where Kalshi’s model wins
- One flat coefficient, identical in every category
- Dollars in from a bank, no wallet to learn
- Free ACH deposits and withdrawals
- A 1099 arrives without you doing anything
Where Polymarket’s model wins
- Lower coefficient in most categories, zero in geopolitics
- Makers pay no fee at all
- No deposit or withdrawal fee, and gas is sponsored
- No company balance to fund in the first place
Two ways to read that table. Kalshi’s flat coefficient is simpler and identical everywhere, which matters if you trade across categories and do not want to think about it. Polymarket comes in cheaper in most categories, free in geopolitics, and free for makers, which matters more if you post resting orders than if you cross the spread.
Neither is a large cost at retail size. The 2% debit card deposit fee on Kalshi will cost most casual users more than their trading fees will, and it is avoidable by using ACH.
Usability
Kalshi is the easier first hour. You sign up, connect a bank, and trade in dollars. Nothing about it requires knowing what a wallet is.
Polymarket asks you to hold a wallet, or to sign up by email and get one created for you. That proxy wallet is a smart contract wallet where you are the sole signer, and you can export the private key at any time. It is more setup, and it buys you something specific, which is the next section.
Markets and liquidity
Kalshi is, in volume terms, mostly a sports exchange. Polymarket’s book is spread across sports, politics and crypto. The two have drifted into different specialities, and the category data makes it obvious.
Pew Research analysed volume since July 2024 and found the mixes are not close. On Kalshi, sports made up 80% of total volume and politics just 4%. On Polymarket, sports were 39%, politics 32% and crypto 20%.
| Share of volume by category | Kalshi | Polymarket |
|---|---|---|
| Sports | 80% | 39% |
| Politics | 4% | 32% |
| Crypto | n/a | 20% |
Pew Research Center analysis of trading volume since July 2024, published May 2026. Categories shown are the largest reported for each platform.
Kalshi still lists economics, politics and culture, but sports is what the volume is. Polymarket is genuinely broad. If you want depth in an election market, a central bank decision, a crypto price level or a geopolitical event, Polymarket is where that liquidity has actually gone. If you want a deep book on a US game tonight, Kalshi has it.
The headline volume numbers follow from that. In July 2026 the three venues combined set a record at $50.59 billion. Kalshi took $37.7 billion of it, roughly 74.5%. Polymarket’s international platform did $7.9 billion and Polymarket US did $5.0 billion, with the US arm growing 54% month over month.
Context matters for those numbers, and most articles quoting them skip it. July 2026 was a World Cup month, and the tournament pushed enormous flow into sports specifically, which is Kalshi’s dominant category. Polymarket’s single largest market that month was the World Cup winner market at roughly $4 billion. Open interest across all three venues fell sharply once the tournament ended.
Which is bigger, and which is better?
Kalshi is bigger. In July 2026 it did roughly three times the volume of Polymarket’s two platforms combined, and it is valued higher: Kalshi raised $1 billion at a $22 billion valuation in May 2026 and has been reported to be seeking new capital at around $40 billion, while Polymarket has been reported to be raising at $15 billion or more.
Why is Kalshi worth more than Polymarket? Mostly because of where US sports volume goes. Kalshi has been onshore and available to US traders continuously since 2020, it is the default venue for the category that drives the most volume in this market, and its dollar rails make it trivial for a US retail user to fund. Polymarket spent years unable to serve US traders at all and only reopened onshore access in December 2025. Being three years behind on the largest single market is enough to explain the gap without either company doing anything wrong.
Bigger is not the same as better for you. Volume tells you where the crowd is, not where your edge is. On a politics or world-events question, Polymarket’s book is deeper and its fee is lower. On a US game, Kalshi’s is. And a lot of active traders simply use both, which is the quietly correct answer for anyone trading across categories.
The comparison that actually decides it for most people is not size at all.
The real dividing line is custody
Custody is the one structural difference between Kalshi and Polymarket. Every other difference in this comparison is a preference.
On Kalshi, Kalshi holds your money. It sits in segregated US bank accounts, it is subject to CFTC rules on customer funds, and Kalshi’s own clearinghouse settles your trades. That is a real and meaningful set of protections, and it is better than most of what this industry has offered historically. It is still a balance on someone else’s ledger. It can be frozen during a verification review, and it is exposed to whatever a court in your state decides next.
On Polymarket, nobody holds your money. In its own words, Polymarket is non-custodial and never takes possession of your funds. Positions and collateral sit in a wallet you control, settlement happens onchain, and resolution runs through the UMA optimistic oracle rather than an internal desk. You can export your private key and walk.
Self-custody is a trade, not a free upgrade, and pretending otherwise would be dishonest. Nobody can freeze your funds, and nobody can recover them either. Lose the key and the money is gone. There is no support ticket for that.
That is the choice. A regulated account someone else administers, or funds you hold and are responsible for. We wrote about why that distinction matters more than it looks in why your exchange became a bank.
A third option: self-custody prediction markets in one app
If the custody question lands you on Polymarket’s side, there is more than one way to get there.
Nika offers prediction markets powered by Polymarket inside a single non-custodial app, alongside spot trading, perpetuals, staking and yield across multiple chains. Same self-custody model, same Polymarket-powered markets, with the rest of your onchain positions in the same place instead of spread across four apps. Nika is not a CFTC-regulated exchange and does not claim to be. If you want regulated dollar event contracts with a 1099 at the end of the year, Kalshi is the better fit and we would say so. If you want self-custody and you would rather not run a separate app for every product, that is the gap Nika fills. More on how Nika’s prediction markets work, and a wider field in the best Kalshi alternatives.
So which should you use?
Choose Kalshi for US sports and dollar funding with the tax paperwork handled. Choose Polymarket for politics, crypto and world events, with self-custody and a lower fee in most categories. Four readers, four answers.
- You want US sports, dollars in and out, and tax paperwork handled. Kalshi. It is the deepest sports book in the category, funding is a bank transfer, and the 1099 shows up in January.
- You want politics, crypto, geopolitics or world events. Polymarket. That is where the liquidity is, the fee coefficient is lower in those categories, and geopolitics carries no trading fee at all.
- You are outside the US. Polymarket, if it is available where you live. Kalshi only serves US-verified accounts, so it is not an option. Check your own jurisdiction first.
- You want to hold your own keys and keep everything in one app. Self-custody options, including Polymarket directly or Nika for Polymarket-powered markets next to spot, perps, staking and yield.
And if you are picking between them purely on trust, we went deeper on the regulated side in is Kalshi legit.
Before you fund anything: the part most comparisons leave out
Most people who trade prediction markets lose money. Both platforms.
An analysis of publicly available Kalshi trade data by the Roosevelt Institute found that ordinary users lost more than $583 million between the platform’s July 2021 launch and May 2026, with sports accounting for roughly $372 million of that. Kalshi has acknowledged that nearly three times as many users lose money as make it. On Polymarket, reporting on trader-level data found that a fraction of one percent of accounts captured around two thirds of all profits.
That is not an argument against either platform. It is how a market with professional participants works, and both companies have been more transparent about it than the industry norm. It is an argument against sizing a position as though you have an edge you have not demonstrated. Trade small until you know which one you are.
Kalshi vs Polymarket: FAQ
What is better, Kalshi or Polymarket? Neither, outright. Kalshi is better for US sports, dollar funding and tax paperwork. Polymarket is better for politics, crypto and world events, charges a lower fee in most categories, and is non-custodial. The decision comes down to who holds your funds, where you live, and what you trade.
How is Kalshi legal but Polymarket is not? Both are legal in the US now. Kalshi has been a CFTC designated contract market since November 2020. Polymarket acquired a CFTC-licensed exchange in 2025 and operates Polymarket US under the same federal framework. What is still pending is Polymarket’s separate application to let US traders use its main international exchange directly.
Which is bigger, Kalshi or Polymarket? Kalshi, by volume. In July 2026 Kalshi did $37.7 billion against $7.9 billion on Polymarket’s international platform and $5.0 billion on Polymarket US. Most of that gap is sports. By category breadth, Polymarket’s volume is spread far more evenly.
Why is Kalshi worth more than Polymarket? Kalshi raised at a $22 billion valuation in May 2026 and Polymarket has been reported raising at $15 billion or more. The gap tracks US sports volume and time onshore. Kalshi has served US traders continuously since 2020, while Polymarket only reopened US access in December 2025.
Does Kalshi actually pay? Yes. Contracts settle mechanically at $1 or $0 when a market resolves, customer funds sit in segregated US bank accounts, and Kalshi Klear, its CFTC-registered clearinghouse, handles settlement. ACH withdrawals are free.
Has anyone made money on Polymarket? Yes, and the distribution is heavily concentrated. Reporting on trader-level data found roughly two thirds of all profits went to about a tenth of a percent of accounts. Most users lose. The same is true on Kalshi.
Can I use both Kalshi and Polymarket? Yes, and many active traders do. Kalshi for US sports and dollar funding, Polymarket for politics, crypto and global events. They are complementary rather than mutually exclusive.
Is Polymarket self-custody? Yes. Polymarket states it is non-custodial and never takes possession of your funds. Positions sit in a smart contract wallet where you are the sole signer, and you can export the private key at any time. Kalshi is custodial by design.
This is information, not financial, legal or tax advice. Prediction markets carry real financial risk, most retail participants lose money, and legal status varies by state and country. Confirm current rules and platform availability before funding any account.
Sources
- CFTC designates KalshiEX LLC as a contract market, November 2020: https://www.cftc.gov/PressRoom/PressReleases/8302-20
- CFTC list of designated contract markets (primary): https://www.cftc.gov/IndustryOversight/TradingOrganizations/DCMs/index.htm
- Polymarket acquires CFTC-licensed QCEX for $112 million, PR Newswire: https://www.prnewswire.com/news-releases/polymarket-acquires-cftc-licensed-exchange-and-clearinghouse-qcex-for-112-million-302509626.html
- Polymarket seeks CFTC approval to reopen its main exchange to US traders, CoinDesk, 28 April 2026: https://www.coindesk.com/policy/2026/04/28/polymarket-seeks-cftc-approval-to-reopen-main-exchange-to-u-s-traders
- Third Circuit affirms Kalshi’s preliminary injunction against New Jersey, Skadden, April 2026: https://www.skadden.com/insights/publications/2026/04/third-circuit-affirms-kalshis-preliminary-injunction
- Third Circuit opinion, KalshiEX LLC v. Flaherty (primary): https://www2.ca3.uscourts.gov/opinarch/251922p.pdf
- Kalshi and Polymarket trading volumes and category mix, Pew Research Center, May 2026: https://www.pewresearch.org/short-reads/2026/05/27/trading-volume-on-prediction-markets-has-soared-in-recent-months/
- Combined July 2026 volume record of $50.59 billion, The Block, 3 August 2026: https://www.theblock.co/news/web3/2026-08-03-kalshi-polymarket-volume-july-410382
- Kalshi raises $1 billion at a $22 billion valuation and targets more, CoinDesk, June 2026: https://www.coindesk.com/business/2026/06/24/kalshi-targets-a-massive-usd40-billion-valuation-widening-lead-over-rival-polymarket
- Polymarket fee schedule by category (primary): https://docs.polymarket.com/polymarket-learn/trading/fees
- Kalshi fee schedule, July 2026 revision (primary): https://kalshi.com/docs/kalshi-fee-schedule.pdf
- Polymarket pUSD collateral and V2 exchange upgrade, 28 April 2026 (primary): https://docs.polymarket.com/concepts/pusd
- Polymarket non-custodial wallets and private key export (primary): https://help.polymarket.com/en/articles/13364260-is-my-money-safe
- Polymarket resolution via the UMA optimistic oracle (primary): https://docs.polymarket.com/developers/resolution/UMA
- How Kalshi is regulated, and Kalshi Klear as a registered clearing organization (primary): https://help.kalshi.com/en/articles/13823765-how-is-kalshi-regulated
- Ordinary Kalshi users lost more than half a billion dollars, Roosevelt Institute: https://rooseveltinstitute.org/blog/since-kalshis-launch-ordinary-users-have-lost-half-a-billion-dollars/
- Most prediction market traders lose money, CNBC, May 2026: https://www.cnbc.com/2026/05/05/gen-z-millennials-prediction-markets.html