Polymarket vs Kalshi: Regulated vs Crypto Prediction Markets
The two largest prediction markets in the world have almost nothing in common under the hood. Here's how to choose.
Polymarket and Kalshi are the two most-watched prediction markets in 2026. Both let you trade binary contracts on real-world events, both saw record volume during the 2024 US election, and both regularly appear in mainstream coverage of election odds. But they are built on opposite philosophies — one crypto-native and offshore, the other US-regulated and fiat-first — and the choice between them changes everything downstream: who can use them, how you fund them, what you can trade, and what happens if something goes wrong.
Regulation
Kalshi is a CFTC-regulated Designated Contract Market (DCM). Every contract it lists has been formally certified or approved by the regulator. Customer funds are held in segregated US bank accounts. Kalshi is legal in all 50 US states after its landmark 2024 court win, which affirmed its right to offer election contracts nationwide despite state-level objections.
Polymarket is unregulated in the US. It settled with the CFTC in 2022 and now blocks US users at the IP and KYC layer. The platform operates through offshore entities; contracts settle on-chain in USDC. There is no US-facing dispute mechanism and no consumer-protection body to appeal to if something goes wrong.
Deposit and withdrawal
Kalshi accepts ACH, debit card, and wire transfers in US dollars. ACH is free and settles same-day for most accounts. Debit deposits are instant with a small fee. Withdrawals go back via ACH and settle in 1–3 business days. There is no crypto exposure at any point — your money is in dollars in a US bank.
Polymarket requires USDC on Polygon. You'll typically bridge from Ethereum or Solana, or buy USDC directly inside Polymarket via Moonpay for a card fee. There are no fiat rails. Withdrawing back to dollars requires selling USDC on an exchange, which adds another fee layer. For US-adjacent international users, this is the biggest friction point.
Contract variety
Polymarket lists thousands of markets: politics, sports, crypto prices, pop culture, weather, awards, and novelty markets like "will X tweet Y by date Z." Many of these would never get CFTC approval — the framework isn't built for that pace of listing. Long-tail markets can be thin, but flagship contracts on elections and major sports have world-class depth.
Kalshi is more curated. Categories include macroeconomics (CPI, Fed decisions, jobless claims), climate, elections, sports, and entertainment. Each contract requires regulatory filing, so the list grows more slowly but is more rigorous — resolution sources are pre-specified, position limits are documented, and there's a paper trail for every listing.
Fees compared
Kalshi charges a per-contract fee that scales with the contract's price and the trader's profit. In practice, expect 1–7% of profit on a winning close. Losing trades incur no additional fee. There are no deposit or withdrawal fees on ACH.
Polymarket has 0% trading fees. You pay the bid/ask spread (typically 1–2 cents on flagship contracts, wider on thin markets) and Polygon gas (fractions of a cent). The real cost is on the on/off ramp — converting USD to USDC and bridging to Polygon adds 0.5–1.5% depending on the route.
Liquidity and depth
Polymarket has higher headline volume — its top election markets have traded billions of dollars. Kalshi has deeper book depth on its largest contracts, often quoting tighter spreads and larger sizes at the top of book. Both platforms thin out quickly outside their flagship markets. If you're moving five figures or more, always check depth before pressing send.
Worked example: same event, both platforms
Suppose both list "Will the Fed cut rates by 25bp at the next meeting?" Kalshi's contract resolves on the FOMC press release timestamp and pays $1 per YES contract; Polymarket's uses the same source but resolves on-chain via UMA. If Kalshi quotes YES at $0.61/$0.62 with 5,000 contracts of depth, and Polymarket quotes $0.60/$0.62 with 20,000 contracts of depth, the platforms are roughly aligned.
A patient trader can arbitrage the gap — buy on the cheaper side, sell on the richer side, and lock in a small edge. This is why prices tend to converge as event time approaches.
When to use which
If you're in the US and want a legal, regulated venue with FDIC-adjacent deposits and clean tax reporting, use Kalshi. If you're outside the US, want the widest market selection, and are already comfortable with crypto rails, Polymarket has more liquidity and more variety. Many sophisticated traders use both — Kalshi as the US-facing rail, Polymarket for international events and novelty markets.
Common pitfalls
Don't assume equivalent markets on both platforms resolve identically. A one-minute difference in the resolution timestamp, or a different data source, can flip a marginal outcome. Read the fine print on each side before running arbitrage.
Don't underestimate the on/off-ramp cost of Polymarket for USD-native users. If you're depositing $500 and withdrawing $500 a month later, ramp fees can eat 1–3% before you place a single trade.