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FundamentalsWhat is a prediction contract?FundamentalsDoes 65¢ really mean a 65% chance?Market mechanicsRead the rules before the headlineMarket mechanicsThe price you see is not always the price you getMarket mechanicsCalculate the return, not just the payoutRisk & rulesThe risks a probability chart leaves out

Compare the contract before the platform

A practical framework for comparing venues without relying on brand names, bonus offers, or headline prices.

Sources checked · Prediction Contracts editorial

Identify the actual provider

Start with the legal entity, jurisdiction, and exact product. A familiar app can route orders to a separate exchange. A brand may also have distinct regional offerings with different terms.

Polymarket’s international and US documentation, for example, are separate sources. Do not apply a fee, access rule, or resolution mechanism from one to the other just because they share a brand.

Verify eligibility and status

Check the current terms for residency, physical location, age, identity verification, and any product restrictions. A website loading successfully does not establish eligibility to trade.

For a US exchange, the CFTC’s designated contract market directory is a primary source for exchange status. The CFTC’s registration guidance points to NFA BASIC for relevant intermediaries and disciplinary history. Verify the exact entity rather than searching only the app’s marketing name.

Match the written terms

Compare event definitions, governing sources, observation periods, thresholds, revision policies, and exceptional outcomes. If these differ, you may be comparing two different exposures.

A hypothetical “rate cut by December” contract differs from “rate cut at the December meeting.” Their prices can differ for a sound reason. Similar headlines do not establish an arbitrage opportunity.

Compare an executable quantity

Use the same intended quantity and comparable timestamps. Estimate the total purchase cost across available price levels, add applicable fees, and inspect the bid available for a potential exit.

A lower headline ask with only a few contracts available may be less useful than a slightly higher ask with sufficient depth. Funding, conversion, and withdrawal costs can also change the comparison.

Evaluate the full lifecycle

A good comparison includes settlement procedures, access to the source evidence, account records, withdrawal processes, and support channels. Evaluate what happens after an order fills, including a disputed or delayed outcome.

We link to official documentation so readers can inspect the terms themselves. This guide is a comparison framework, not a ranking or an endorsement. Recheck time-sensitive details immediately before relying on them.

Sources & further reading

  1. CFTC — Designated contract market directory
  2. CFTC — Check registration and backgrounds
  3. Polymarket — Geographic restrictions for the international platform
  4. Polymarket US — Fee schedule
  5. Polymarket international — Trading fees

Platform terms and rules can change. Check the linked primary sources and the specific contract before relying on a detail. How we work →