Prediction Market Comparison: Polymarket vs Kalshi vs Robinhood

Polymarket, Kalshi, and Robinhood all let users trade on whether an event will happen, but they are not the same type of market and do not simply offer the same contract through different interfaces.

Polymarket itself has an international platform and a separate CFTC-regulated Polymarket US venue. Kalshi directly operates a designated contract market. Robinhood mainly acts as a broker and retail interface, routing customers to partner exchanges such as KalshiEX, ForecastEX, or Rothera.

The important differences are who lists the contract, where funds are held, who determines the result, how disputes work, and whether a user is eligible in a particular jurisdiction.

This comparison reflects official information checked on July 12, 2026. Fees, access rules, and product availability change, so the specific market page remains controlling.

How event-contract prices work

Most prediction markets frame a question as Yes and No contracts. A Yes contract trading at $0.65 is commonly read as an implied probability of about 65%, but it is not a guaranteed statistical forecast. The price also reflects liquidity, spread, fees, position limits, and the mix of participants.

At settlement, a correct contract generally pays $1 and an incorrect contract pays $0. Traders can also exit before resolution. Profit is the difference between the entry price and the sale or settlement value, after quantity and costs. Correctly predicting an outcome does not mean earning a full dollar per contract.

Three brands, four distinct routes

Route	Legal and market structure	Funding and interface	Resolution	Access boundary
Polymarket international	International platform; officially described as separate from CFTC regulation	Wallet and USDC-centered onchain experience	Market rules plus UMA Optimistic Oracle proposal and dispute process	Many restricted jurisdictions; the international venue blocks the U.S.
Polymarket US	QCX LLC d/b/a Polymarket US, a CFTC-designated contract market	Separate regulated U.S. venue	DCM rules and contract-specific terms	International rules should not be assumed to apply
Kalshi	CFTC-designated contract market matching member orders	Account-based; supported bank, card, crypto, and wire routes	Contract rules, named source agencies, and market determination	Identity verification and jurisdiction limits apply
Robinhood Prediction Markets	Robinhood Derivatives acts as an FCM/broker; contracts come from partner exchanges	Integrated into a Robinhood brokerage account	The exchange listing the contract resolves it under its rules	Approved U.S. residents; state and contract limits may apply

Robinhood is therefore not simply a third standalone prediction exchange in this comparison. It is a distribution layer for several regulated event-contract venues.

Polymarket: onchain visibility and broad event coverage

Polymarket's international platform combines wallet-based funding, a central limit order book, and smart-contract settlement. It covers politics, macroeconomics, technology, crypto, culture, sports, and geopolitical events.

Resolution follows the written market rules and the UMA Optimistic Oracle. A proposed result enters a challenge window. A challenger can post a bond and trigger a dispute and voting process.

This makes the process observable and contestable, but it does not eliminate risk:

• contract wording and source definitions can still be ambiguous;
• disputed markets can take longer to settle;
• users manage wallets, keys, USDC, network transactions, and approvals;
• thin order books can move sharply on small trades;
• strict geographic restrictions apply, and VPN evasion is prohibited.

Polymarket US is a separate CFTC-designated contract market. Polymarket's own site says the international and U.S. platforms operate through separate legal entities. Account, funding, product, and resolution assumptions should not be carried from one to the other.

Kalshi: direct access to a regulated event exchange

Kalshi operates a CFTC-designated contract market and matches users with other members. The exchange is not permanently taking the Yes or No side.

Each market has rules defining the measured value, time window, source agency, and determination criteria. Many markets settle within hours of an official result, but settlement can take longer when a source is delayed, data are revised, or the contract specifies a later determination time.

Common advantages include a regulated account structure, multiple funding routes, explicit source agencies, and markets spanning economic data, weather, politics, sports, culture, and technology.

Important limitations include identity verification, jurisdiction and contract restrictions, fees that vary by contract and the current fee schedule, and a difference between market close time and determination time. A later revision by a source does not necessarily reopen a market that has already settled.

Robinhood: a broker interface, not one resolution venue

Robinhood Derivatives offers event contracts to eligible customers, but the underlying contract may be listed by KalshiEX, ForecastEX, or Rothera. Robinhood presents a unified interface while the exchange and rulebook can differ underneath.

That matters because:

1. the listing exchange controls the contract rules and resolution;
2. total cost can include both Robinhood commission and exchange fees;
3. a market visible in Robinhood was not necessarily designed or resolved by Robinhood.

Since June 1, 2026, Robinhood has used a probability-weighted commission formula. Commissions are highest near a $0.50 price and lower near $0 or $1, with a stated cap of $0.01 per contract. Gold and non-Gold parameters differ, and an exchange may add a fee. The order preview is more reliable than an older flat-fee article.

Current eligibility generally requires age 18 or older, U.S. residency, an individual brokerage account, and approval for Robinhood Derivatives. State and contract-specific limits also apply.

Why headline fees are not enough

The total cost of a prediction trade can include:

• platform or broker commission;
• exchange or protocol fee;
• bid-ask spread;
• slippage and market impact;
• deposit, currency conversion, card, or intermediary charges;
• gas and bridging costs;
• the opportunity cost of funds awaiting settlement.

Polymarket international enables taker fees by market category while makers are generally free and some categories are fee-free. Kalshi uses its live fee schedule and contract-specific rules. Robinhood charges its probability-based commission and may pass through an exchange fee.

A nominally fee-free market with a four-cent spread may be more expensive than a market with a one-cent fee and tight depth. Compare the same event, time, and order size on an all-in execution basis.

The resolution chain matters more than the headline

Before trading, identify:

1. the exact event definition;
2. the deadline and timezone;
3. the designated source;
4. fallback rules for delay, revision, or source failure;
5. the dispute, invalid-market, and exceptional-settlement process.

A candidate declaring victory is different from official certification. A product announcement may not satisfy a contract requiring public availability. An economic threshold may use an initial release or a later revision.

Polymarket international uses written rules and UMA disputes. Kalshi uses market rules, source agencies, and exchange determination. Robinhood users must trace the contract to the actual partner exchange. Identical Yes/No labels do not imply identical resolution paths.

Liquidity determines how informative the probability is

A $0.70 price can be read as roughly 70% implied probability only within the market's liquidity and rule context.

Check:

• the bid-ask spread;
• average execution price for the intended size;
• whether the latest trade was tiny;
• whether the position can be sold before settlement;
• whether related markets imply contradictory outcomes;
• whether close-only or trading halts may occur.

A market price is a tradable consensus under specific rules, not an error-free probability supplied by an independent authority.

Geographic restrictions are not a technical obstacle to bypass

Polymarket international maintains a restricted-location list and prohibits VPN evasion. Polymarket US is a separate regulated route. Kalshi is available to some international users but requires identity checks and retains jurisdiction restrictions. Robinhood event contracts primarily require eligible U.S. residents and can face state-level limits.

Check physical location, residency, account entity, and the specific contract. A website loading is not proof of eligibility. This article does not provide methods to bypass KYC, geoblocking, or account rules.

Which route fits which research need

Need	Start with	Why
Observe global political, crypto, and technology expectations onchain	Polymarket international	Broad markets and observable onchain workflow
Trade directly through a regulated event exchange	Kalshi	Direct DCM structure and named source rules
Use an existing U.S. retail brokerage interface	Robinhood	Simple broker access across partner venues
Research the regulated U.S. Polymarket product	Polymarket US	Separate CFTC-designated market

This is not a performance ranking. Availability, spread, rule quality, and eligibility matter more than brand preference.

Ten checks before placing an order

1. Which legal entity and exchange am I actually using?
2. Is the product permitted in my location?
3. Have I completed required identity and account approval?
4. What exactly do Yes and No mean, including time and source?
5. How are conflicting sources or revisions handled?
6. What are the current spread and expected slippage?
7. What is the all-in cost including commission, exchange, funding, and network charges?
8. Can I exit before settlement, and can the market become close-only?
9. Who holds the funds and controls the private keys?
10. Can I tolerate a zero payout or delayed resolution?

Rule quality matters more than market count

Polymarket international, Polymarket US, Kalshi, and Robinhood solve different access and market-structure problems. No venue is automatically best for every jurisdiction, event, and order size.

A better sequence is to confirm the legal route, read the complete contract rules, inspect liquidity and total cost, and only then decide whether the price is useful. For readers who use prediction markets as information rather than as a trading venue, comparing identically defined events across markets is often more valuable than reacting to every one-point price move.

Information checked: July 12, 2026.

• Polymarket international and Polymarket US entity disclosure
• How Polymarket resolves markets through UMA
• Polymarket geographic restrictions
• Kalshi market rules
• Kalshi settlement timing
• Robinhood event contracts, fees, and eligibility
• CFTC designated contract markets
• CFTC prediction-market enforcement advisory

This article is for education only and is not investment, legal, gambling, or tax advice. Event contracts can lose their full purchase price because of an incorrect view, illiquidity, ambiguous rules, fees, access restrictions, or disputed settlement.