The 4 biggest differences between Kalshi and Polymarket

• Kalshi and Polymarket are the two biggest prediction markets in the world.
• They’re often spoken about in tandem — but there are some key differences between them.
• That includes regulation, how they operate, and what kinds of trades they offer.

If you’ve ever wondered how Polymarket and Kalshi are different, you’re probably not alone.

The two prediction market giants are often spoken about in the same breath, and they largely serve the same purpose: allowing people to trade on the probability of real-world events.

They’ve also both exploded in popularity in recent years, partnered with major institutions such as sports leagues, award shows, and media organizations, and engaged in attention-grabbing stunts to build their brands.

But there are some crucial differences between Kalshi and Polymarket that you should be aware of. Here’s what to know.

Kalshi is fully regulated by the federal government. Polymarket is mostly not.

Kalshi is regulated by the Commodity Futures Trading Commission, the federal agency that oversees derivatives markets in the US.

When people say “Polymarket,” they usually refer to the company’s international platform, which is not CFTC-regulated. That platform is technically run by an entity based in Panama, though the company’s offices are based in New York.

Polymarket is rolling out a platform for American users called Polymarket US, which is CFTC-regulated. But as of now, it is invite-only and features just sports contracts.

There are many implications of being regulated by the CFTC, but perhaps the biggest for the average prediction market user is that while Americans can legally trade on Kalshi, they cannot do so on the international Polymarket platform.

However, many Americans use VPNs to bypass that prohibition and trade on Polymarket’s international platform anyway.

Polymarket uses crypto, allowing for the public tracking of individual trades

Another big difference between the two prediction markets is that individual trades are public on Polymarket.

That’s because Polymarket uses USD Coin, a stablecoin pegged to the US dollar, on the Polygon blockchain.

Anyone can see the value of individual Polymarket users’ trades, along with when they made those trades and how much they ultimately profited.

On Kalshi, individual trading activity is private and takes place in regular US dollars.

That’s part of why individual suspicious Polymarket trades — including those on former Venezuelan President Nicolás Maduro and the prospect of war in Iran — have generated so much public attention.

However, there’s a flipside. Individuals can trade anonymously on Polymarket, while Kalshi requires users to provide personal identifying information when they register.

That means it’s actually easier to identify potential insider traders on Kalshi than on Polymarket, though law enforcement may still be able to identify Polymarket users by tracing how the crypto wallets were funded.

Polymarket allows betting on a wider range of topics

On Polymarket, you can bet on war. On Kalshi, you can’t.

That’s because the CFTC, which regulates Kalshi, is authorized by federal law to prohibit the company from offering prediction markets involving trades that are “contrary to the public interest,” including terrorism, assassination, war, and gaming.

Polymarket, on the other hand, is not subject to those same restrictions.

This is a point that Kalshi has been eager to emphasize, particularly as prediction markets face more scrutiny from federal lawmakers.

The company recently posted ads around Washington, DC highlighting that Kalshi doesn’t “do death markets.”

At the same time, those restrictions have sometimes put Kalshi in a tough spot.

After the killing of Iranian Supreme Leader Ali Khamenei in February, the company partially paid out users who had bet that the Ayatollah would be “out” as leader by a certain date.

That’s because, per CFTC regulations, the company can’t host what it’s dubbed a “death market,” so Khamanei’s death could not count as him being “out.”

While that had been specified in the rules for that market, many users were unaware and became angry with Kalshi. The company later reimbursed users for fees on the market and has since made those rules more prominent.

Yet Polymarket has also caught flak for its more wild-west variety of markets, and the company recently took down a market on whether a nuclear detonation would take place in the near future.

Each platform resolves markets differently

Eventually, any event you’re trading on will either happen or not. This is when the market “resolves.”

On Kalshi, each market has a set of rules specifying the conditions under which it resolves to “yes” or “no.” Once trading closes, Kalshi makes an official decision on how the market will be resolved.

Polymarket, on the other hand, uses a system called UMA Optimistic Oracle, in which disputed outcomes are resolved by a vote taken by a group of cryptocurrency tokenholders.

In practice, this typically means little for users, but in some cases it can lead to differing outcomes, such as when Kalshi and Polymarket disagreed over whether Cardi B technically “performed” at the 2026 Super Bowl halftime show.