Kalshi vs Polymarket: which should you use?

Kalshi vs Polymarket at a glance

On paper, they look like twins. Both run CFTC-regulated US exchanges, each with its own clearinghouse. The table shows where they part.

One note first. For Americans, “Polymarket” means Polymarket US, so its column shows that app. The international crypto site comes up in the next section.

The real difference between Kalshi and Polymarket

It is not the exchange. Both run one, and both answer to the CFTC. The difference is in the name: “Polymarket” is two products.

Polymarket US trades on QCX, a CFTC-designated exchange since July 9, 2025, and opened to Americans in December 2025. The international site, polymarket.com, runs on crypto and is close-only from the US.

Kalshi is one product. The CFTC designated its exchange on November 3, 2020, and registered its clearinghouse, Kalshi Klear, in August 2024.

So for an American, the choice is Kalshi or Polymarket US. Both publish prices and charge takers on the same curve. The edges decide it: funding, interest, withdrawal rules and legal fights.

The same market, priced on Kalshi and Polymarket

Tampa Bay Rays vs. Milwaukee Brewers

Milwaukee Brewers: price on each venue, the fee, 24h volume and liquidity, with a link to trade

Venue	Milwaukee Brewers	Tampa Bay Rays	Fee	24h volume	Liquidity
PolymarketClose-only for US residents	53¢cheapest to buy	48¢	1.2¢	$129K	$693K	Trade →
Kalshi$50 bonus	54¢	47¢	0.4¢	$1.4M	–	Trade →

Updated 22:33 UTCFee: the taker fee on one contract at the price shown, as each venue publishes it; Polymarket’s is its international book.

This is the comparison no venue will show you: one question, both prices, side by side. The Polymarket price here comes from its international order book.

Polymarket US runs a separate book, so its price can differ. And read both rules before you compare. The same question can settle on different sources, and that decides who gets paid.

Kalshi vs Polymarket fees on the same $100 trade

For takers, it is nearly a tie. Kalshi's curve uses 0.07, Polymarket US's 0.0695. On $100 at 50¢, that is $3.50 against $3.48.

Makers are where they part. Kalshi charges resting orders 0.0175 on some series. Polymarket US charges makers nothing. From October 19, 2026, only makers trading $10 million or more a month earn a rebate. Takers trading $250,000 or more a month get 3% to 30% of their fees back.

Moving money costs differ too. Kalshi's bank, wire and real-time transfers are free, while debit cards can cost 2%. Polymarket US publishes no deposit fee, and withdrawals are free.

Every rate is on our Kalshi fees and Polymarket fees pages.

Is Kalshi or Polymarket legal in the US?

Both, at the federal level. Kalshi has been a CFTC-designated contract market since November 2020. Polymarket US trades on QCX, designated in July 2025.

By our state records: Kalshi’s contracts are restricted or contested in 19 states. Polymarket’s contracts are restricted or contested in 15 states. Each state's page is on our prediction market legal hub.

The old question, “how is Kalshi legal but Polymarket isn't,” dates from 2022. That January the CFTC fined Polymarket $1.4 million for unregistered markets, and it blocked Americans. It came back in December 2025, through Polymarket US.

State law is where the fights are. Nevada has court orders against both. New York is suing both: Kalshi since July 31, 2026, and Polymarket US since September 24. Missouri's attorney general sent both cease-and-desist letters on September 16. The office has posted no further action since.

The court record splits by venue. Kalshi won in the Third Circuit against New Jersey, then lost in the Ninth and the Sixth. On October 9 it asked the full Sixth Circuit to rehear its case. Polymarket US lost in Nevada, but helped pause Minnesota's ban in July.

Appeals courts are split on whether states can act at all. On October 9, 2026, the CFTC proposed a rule defining event contracts, sports included, as swaps. Every case is on our prediction market legal tracker.

Kalshi or Polymarket: which is safer?

On money, they are close. Both keep US customers' cash at a CFTC-registered clearinghouse, apart from company funds. Kalshi's is Kalshi Klear; Polymarket US's is QC Clearing.

Neither balance is FDIC- or SIPC-insured. On both, segregation is the protection, not insurance.

The fine print differs. Polymarket US's participant agreement lets its clearinghouse commingle or invest customer cash, within CFTC rules. Kalshi Klear may not mix members' funds with its own.

Both check ID. Polymarket US lists the full Social Security number as a required field. Kalshi may ask for it later, but you can trade and bank out without it.

Both carry a record. Kalshi faces class actions over its sports contracts and its Khamenei market. Polymarket has the 2022 CFTC penalty and a 2026 report of paid fake-win videos. None of these cases claims either took deposits and vanished.

Our reviews answer is Kalshi legit and is Polymarket legit in detail.

Kalshi vs Polymarket markets and volume

In the last 24 hours, Kalshi traded $134.8M and Polymarket $76.5M, by each venue's own market data. That is across 162,041 open markets on Kalshi and 205,384 open markets on Polymarket.

Both list all six categories we track: sports, politics, economics, crypto, culture and climate. Both split one question into many strikes and dates, so a market count is not a count of questions.

Polymarket's figures here come from its international site. Polymarket US trades on a separate book and publishes no 24-hour volume. Its prices are in our live prediction market odds. Compare daily totals on our prediction market volume page.

Market counts are not depth. A market with thin bids can cost more to exit than any fee. Check the order book first, and post limit orders where you can. Both venues let orders rest on the book.

Deposits, withdrawals and payouts on Kalshi and Polymarket

Kalshi takes ten ways in. They include bank and real-time transfers, debit cards, Apple Pay, Google Pay, PayPal, Venmo, Cash App, wire and crypto. Polymarket US takes seven: debit card, bank transfer, PayPal, Venmo, wire, and Apple Pay or USDC on iPhone.

Getting money out follows different rules. Kalshi pays out to a debit card, bank, PayPal, Venmo or crypto wallet, with no Kalshi fee. Polymarket US repays the method you funded from, oldest deposit first.

Timing differs too. Kalshi card withdrawals are normally instant, and bank transfers take a few business days. Polymarket US card and bank withdrawals take 3 to 4 business days. Wires take about 1, but only support can send one.

Holds differ too. Kalshi may hold deposited cash for up to 2 days after it settles, if it leaves by another method. Polymarket US keeps card and bank deposits until they clear, including profits made with them.

Winning contracts pay $1 on both. Most Kalshi markets settle within hours of the result. Polymarket US sports markets often resolve shortly after the official result.

Settlement and disputes

Rules decide who gets paid. Kalshi and Polymarket US both settle from the sources named in each market's rules, under CFTC oversight. Kalshi's Khamenei market shows why: it paid the last price before his death, not $1.

Polymarket's international site works differently. It settles through UMA, a crypto oracle. A proposed result stands after 2 hours unless someone disputes it. Disputes go to a vote of UMA token holders.

That vote has gone wrong before. In March 2025, traders accused one large UMA holder of swinging a $7 million market. Polymarket said it could not issue refunds.

Kalshi and Polymarket apps and support

Kalshi: App Store 4.8 (614K) · Google Play 4.7 (141K). Polymarket US: App Store 4.5 (62K) · Google Play 3.7 (13.9K). Ratings read October 19, 2026.

Both run on iOS, Android and the web. Kalshi adds a desktop terminal, Kalshi Pro, and both offer an API.

Logging in differs. Polymarket US has no password: you sign in with Google or Apple. Kalshi uses a password and asks for a two-factor code at least every 30 days.

So do combos. Kalshi prices them by request for quote, and a filled combo cannot be reversed. Polymarket US combos join 2 to 10 markets, and every leg must win.

Polymarket US also pauses for maintenance on Thursdays, from 6 to 8 a.m. Eastern, and cancels open orders first. Since October 15, deposits and withdrawals pause then too. Support on both is chat and email, and neither lists a phone line.

Can you use Kalshi and Polymarket together?

Yes. Nothing stops an American holding accounts on Kalshi and on Polymarket US.

Arbitrage is harder than it looks. To lock in a profit, one venue's Yes plus the other's No must cost under $1, after both fees.

At 50¢, taker fees on the two add about 3.5¢ a contract pair, so the gap between the prices must beat that. Right now we match 1,586 questions listed on both.

Then check the rules. Two markets can look identical and settle on different sources or dates. A “risk-free” pair can pay out on neither side. We match questions listed on both in our live prediction market odds.

Kalshi or Polymarket: which should you pick?

On our published method, Kalshi ranks first of 15 apps at 4.9 out of 5. Polymarket US ranks third, at 4.7. Your own use decides it.

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