Polymarket
A decentralized prediction market platform that enables individuals to speculate on the outcomes of future real-world events. Built on the Polygon blockchain, it offers transparent, peer-to-peer trading across politics, sports, and economics.
⬌ How Polymarket compares to Kalshi on fees, access and settlement — a dated comparison with both fee formulas, who can actually trade in which country, and how each venue settles.
⬌ How Polymarket compares to Robinhood on pricing, access and market coverage — pricing notes, access, platforms and eligibility for both, with the date each record was last verified.
$Pricing Details
Free to use. Taker fees only, set by market category (0.04-0.07 on the p*(1-p) curve); makers pay nothing. No resolution fee. Verified 2026-10-21 against Polymarket's fee documentation.
⬡Eligibility
Two products with separate eligibility. polymarket.com is the international, crypto venue: signup is an email address or a self-custody wallet, and trading is closed to US IPs, which the geoblock documentation classes as close-only on both frontend and API, alongside a long restricted list that includes the UK, Germany, France, Australia, Brazil, Singapore, Thailand and four Canadian provinces, with OFAC-sanctioned countries blocked outright. polymarket.us is the US venue, operated by QCX LLC as a CFTC-designated contract market: US residents open an account in the app and must pass KYC (legal name, residential address, date of birth, phone, Social Security number, plus a government ID and selfie check if the automated check asks for more) before they can deposit or trade. Eligibility is not the same as legality: the geoblock endpoint is the operational test for the international venue, and state courts are still contesting the US product. Sources: Polymarket Documentation, 'Geographic Restrictions'; Polymarket US Documentation, 'Create an Account' and 'What is Polymarket US?'; checked 2026-10-21.
⌘Data and API access
Documented for both venues. The international stack at docs.polymarket.com is split into a Gamma API (gamma-api.polymarket.com) for events and market metadata, a CLOB API (clob.polymarket.com) for order-book reads and order placement, a Data API v2 for positions, activity and leaderboards, WebSocket streams for market and account events, and a geoblock endpoint that reports whether the caller's IP may trade. Public reads need no key; trading is signed by the account's signer key. Polymarket US has its own documented API at docs.polymarket.us: a keyless public gateway (gateway.polymarket.us) for markets, events and search, and an authenticated api.polymarket.us for orders, portfolio and balances with two WebSocket streams, keys issued through the app after identity verification. Sources: docs.polymarket.com, 'Overview' and 'Geographic Restrictions'; docs.polymarket.us, 'Introduction' and 'Authentication'; checked 2026-10-21.
✦Features
- › Binary Markets
- › Order Book
- › Limit Orders
- › AMM Pools
- › Permissionless Market Creation
- › Fiat On-ramp
±Good for, not good for
- › Crypto-native trading on Polygon: non-custodial, USDC collateral, settlement visible on-chain
- › Building on documented APIs: Gamma, CLOB and Data for the international venue, a public plus authenticated API for the US one
- › Trading from most countries outside the geoblock list without a brokerage account or USD bank rails
- › US residents who specifically want a CFTC-regulated, USD venue, which is what polymarket.us is
- – US traders who want polymarket.com: the international venue is close-only for US IPs and its API rejects orders from blocked regions
- – Privacy from KYC at the US venue: Polymarket US wants SSN, date of birth and a government ID before you can deposit
- – Anyone in a close-only jurisdiction such as the UK, Germany, France, Australia or much of Canada who wants to open new positions