Polymarket vs Kalshi: How the Top Prediction Markets Compare

If you've decided to try prediction markets, two names come up first: Polymarket and Kalshi. They let you do the same basic thing — buy and sell shares in real-world outcomes — but they're built on opposite philosophies. One is crypto-native and self-custodial; the other is a regulated US exchange that works like a brokerage. This guide breaks down the differences so you can tell which fits you. If you're new to the concept, start with What are prediction markets? first.

Polymarket at a glance

Polymarket is the largest crypto-native prediction market.

• How you fund it: You deposit USDC, a dollar-pegged stablecoin, into a crypto wallet. Trades settle on a low-cost Ethereum network (Polygon).
• Who holds your money: You do. Funds stay in your own wallet and in smart contracts, not in a company account.
• How outcomes are decided: Through a decentralized oracle that reports results on-chain, with a dispute process if a result is challenged.
• Range of markets: Very broad and fast-moving — politics, economics, crypto prices, sports, and culture. New markets appear quickly around current events.
• Who it suits: People already comfortable with crypto wallets and stablecoins who want the widest, most liquid set of markets.

Kalshi at a glance

Kalshi is a US-based exchange regulated by the Commodity Futures Trading Commission (CFTC).

• How you fund it: Ordinary US dollars via bank transfer or card — no crypto required.
• Who holds your money: Kalshi, as a regulated exchange, similar to a brokerage.
• How outcomes are decided: By the exchange under its published rules and regulatory oversight.
• Range of markets: Wide and growing, but operating inside a US regulatory framework.
• Who it suits: US users who want a regulated, dollar-based experience and would rather not touch crypto at all.

The key differences

The two platforms diverge on a few decisions that matter:

• Custody. Polymarket is self-custodial — you hold your funds and bear the responsibility that comes with that. Kalshi custodies funds for you under regulatory rules.
• Funding rail. Polymarket runs on stablecoins and a blockchain; Kalshi runs on the traditional banking system.
• Regulation. Kalshi is a CFTC-regulated exchange. Polymarket is a decentralized protocol; its availability and legal status differ by jurisdiction and have changed over time.
• Eligibility. Access rules for both have shifted repeatedly and depend on your country and US state. This is the single most important thing to check before you start, because it changes often.
• Fees and spreads. Both can charge fees, and you also pay an implied cost through the bid-ask spread, which is wider on thin markets. Read each platform's current fee schedule rather than assuming.

Which is right for you?

• If you already use crypto, want the broadest and most liquid markets, and value self-custody, Polymarket is the natural starting point.
• If you're in the US, want a regulated venue, and prefer funding with dollars from your bank, Kalshi will feel more familiar and lower-friction.

Many active users watch both, because the same event can be priced slightly differently on each, and a market that's liquid on one may be thin on the other.

Risks and a reality check

Whichever you choose, the fundamentals from our main guide still apply: a losing position goes to zero, thin markets are volatile and hard to exit, and resolution can occasionally be disputed. Self-custody on Polymarket also means you're responsible for your own wallet security — there's no support line to reverse a mistake. Regulated venues like Kalshi reduce some of that operational risk but add their own account and eligibility rules.

Size your positions accordingly, and only commit money you're prepared to lose entirely.

Key takeaways

• Polymarket is crypto-native, self-custodial, and funded with USDC; Kalshi is a US CFTC-regulated exchange funded with dollars.
• The big trade-offs are custody, funding rail, and regulation — pick based on which you're comfortable with.
• Eligibility rules change often and vary by location; confirm access for your region before signing up.
• Both charge fees and have spreads; thin markets cost more to enter and exit.
• This is speculation with real downside on either platform — not financial, legal, or investment advice.