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Polymarket FAQ

Updated September 25, 2026 · 148 questions

Short answers to 148 questions people ask about Polymarket, from whether it is legal where you live to fees, payouts, disputes, how accurate its odds are and how it compares with Kalshi. Each answer comes from the page on this site that covers the topic in full, with its sources and dates, and is updated with that page.

Is Polymarket legal? Access and the US (9) · Fees, payouts and resolution (27) · Odds and accuracy (25) · How the different markets work (39) · Polymarket compared (19) · Data, citing and tools (29)

polymarket.com does not let US users open new positions. Polymarket US, the CFTC-regulated app, is reported available in 44 of the 50 states and D.C., not available in 1 and unclear in 6 (as of September 25, 2026). Several states are suing prediction-market companies, so check the dated timeline on each state's page. Not legal advice. More: Is Polymarket legal in your state?

Can Americans use polymarket.com?

Not for new trades: its help center lists the United States as blocked and its developer documentation as close-only; US residents are pointed to Polymarket US, the CFTC-regulated app. More: Is Polymarket legal in your state?

What are Polymarket US fees?

Takers pay 0.0695 x contracts x p x (1-p), at most $1.74 per 100 contracts at 50 cents; makers get a rebate of 0.0125 x contracts x p x (1-p); withdrawals are free. More: Polymarket US: is Polymarket legal in the US?

Can I use my Polymarket.com account in the US app?

No. Polymarket says US residents must use the separate Polymarket US app and the accounts are not connected. More: Polymarket US: is Polymarket legal in the US?

How do I deposit on Polymarket US?

By debit card or ACH (up to $50,000 a day each) or by wire from $1,000, from accounts in your own name; withdrawals return to the same source. More: Polymarket US: is Polymarket legal in the US?

Which countries are banned from Polymarket?

Fully blocked: Iran, Syria, Cuba, North Korea, and Ukraine's Crimea, Donetsk and Luhansk regions. Dozens more are close-only; see the table. More: Where is Polymarket available? Restricted countries list

Is Polymarket available in the United States?

polymarket.com is close-only for US users. Polymarket separately launched a US app in December 2025 after CFTC approval; access to it depends on the state. More: Where is Polymarket available? Restricted countries list

What does close-only mean?

You can close positions you already hold but cannot open new ones from that location. More: Where is Polymarket available? Restricted countries list

How does Polymarket check my location?

Its website and API check where each request comes from, and its terms of service forbid using a VPN to get around restrictions. More: Where is Polymarket available? Restricted countries list

Fees, payouts and resolution

Does Polymarket charge trading fees?

Yes, on most markets: the taker (the order that fills against a resting order) pays a fee of shares × fee rate × p × (1 − p). The rate depends on the market's category. Geopolitical and world-events markets, and some single games, have no fee. More: Polymarket Fees and Fee Calculator

How is the Polymarket fee calculated?

Multiply the number of shares by the market's fee rate and by p × (1 − p), where p is the price. The fee is largest in dollars at 50¢ and shrinks toward 0¢ and $1. Example: 100 shares at 50¢ in a 4% market cost 100 × 0.04 × 0.25 = $1.00 in fees. Fees are rounded to 5 decimal places. More: Polymarket Fees and Fee Calculator

Do makers pay fees on Polymarket?

No. Makers are never charged; only takers pay. Polymarket also returns part of the taker fees to makers through its maker rebate program — the share for each category is in the table on this page. More: Polymarket Fees and Fee Calculator

Are fees charged on both buying and selling?

The fee applies whenever you take liquidity, whether you buy or sell, and it is calculated the same way in both directions. More: Polymarket Fees and Fee Calculator

Does Polymarket charge for deposits or withdrawals?

Polymarket's documentation says USDC deposits and withdrawals carry no Polymarket fees. A wallet, exchange or bridge you use on the way may charge its own network or service fee. More: Polymarket Fees and Fee Calculator

How does Polymarket decide the outcome of a market?

Through UMA's optimistic oracle: anyone proposes the result with a bond, and if nobody disputes it within two hours the market resolves. Disputes lead to a new proposal round and, if disputed again, a UMA token-holder vote. More: How Polymarket Markets Resolve

How long does Polymarket take to pay out?

About two hours after an undisputed proposal. Disputed markets take roughly four to six days because of the extra proposal round and the roughly 48-hour UMA vote. More: How Polymarket Markets Resolve

Can Polymarket change the rules of a market?

Polymarket can publish additional context to clarify an ambiguous question, but its documentation says a clarification cannot change the question's fundamental intent. More: How Polymarket Markets Resolve

How long does Polymarket take to resolve a market?

In our sample the median market was settled 3.5 h after its scheduled end; 93% within a day and 98% within a week. Disputed markets take longer: median 4 days. More: How long does Polymarket take to resolve?

How often are Polymarket resolutions disputed?

3.6% of the markets settled through UMA in our sample had at least one dispute; 72 had two or more. More: How long does Polymarket take to resolve?

Can a Polymarket market resolve before its end date?

Yes. 20% of the markets in our sample closed more than an hour before their end date, usually “by a date” questions whose event happened earlier. More: How long does Polymarket take to resolve?

What is the spread on Polymarket?

The gap between the best ask (lowest sell price) and the best bid (highest buy price). Liquid markets often trade with a 1¢ spread; thin markets can be several cents wide. More: How to Read a Polymarket Order Book

Why does the Polymarket price differ from what I pay?

The displayed probability is the midpoint of the spread (or the last trade when the spread is wide). A market buy pays the ask — and more if your order is larger than the shares offered at the best price — plus any taker fee. More: How to Read a Polymarket Order Book

How do I avoid slippage on Polymarket?

Use limit orders at the price you want, split large orders, and check the depth first: the table above shows what spending $100 to $50,000 would cost right now. More: How to Read a Polymarket Order Book

Do I get my money back if a Polymarket market is canceled?

Not as a refund. The market resolves under its rules; for a canceled event that is often 50-50, which pays $0.50 per Yes or No share, so you gain or lose depending on the price you paid. More: What happens when a Polymarket market is canceled?

What does 50-50 mean on Polymarket?

It is a rare resolution used when neither Yes nor No applies, for example a game canceled with no make-up date. Each Yes and each No share then redeems for $0.50. More: What happens when a Polymarket market is canceled?

What happens if a game is postponed?

Sports rules usually keep the market open until the game is completed. It resolves 50-50 only if the game is canceled with no make-up game or, in some sports, if there is no result by a stated deadline. More: What happens when a Polymarket market is canceled?

Can Polymarket change the rules after I buy?

It can add clarifications, which its documentation says cannot change the fundamental intent of the question. A clarification clears the order book and cancels resting orders. More: What happens when a Polymarket market is canceled?

How long does payout take after a market ends?

About two hours after an undisputed proposal and roughly four to six days if the result is disputed, according to Polymarket's documentation. More: What happens when a Polymarket market is canceled?

What does “Other” mean on Polymarket?

It is the catch-all outcome in a multi-outcome market. It resolves Yes if the winner is not one of the named outcomes, or in any case the rules assign to it, such as no result by a deadline. More: What does “Other” mean on Polymarket?

Why does Polymarket say not to trade “Other”?

In markets that add names over time, what “Other” covers narrows each time a placeholder is named, so a share can end up covering fewer outcomes than when it was bought. Polymarket's documentation advises trading named outcomes only. More: What does “Other” mean on Polymarket?

Is “Other” the same as a 50-50 resolution?

No. A 50-50 resolution is a separate, rare result used when neither Yes nor No applies, and it pays $0.50 per share. “Other” is an outcome that pays $1 per share if it wins. More: What does “Other” mean on Polymarket?

Has “Other” ever won on Polymarket?

Yes. It won TIME's 2025 Person of the Year market after TIME named the “Architects of AI”, and the 2024 next French prime minister market when Michel Barnier was appointed. More: What does “Other” mean on Polymarket?

Does Polymarket make money when traders lose?

No. Its documentation says prices come from users trading with each other on an order book, and its trading income is the fee charged on trades, whichever side wins. More: How does Polymarket make money?

Is Polymarket profitable?

It does not say. Polymarket is private and publishes no audited results; the figures reported in 2026 are revenue run rates of more than $1 billion a year, with no profit numbers. More: How does Polymarket make money?

Who has invested in Polymarket?

Disclosed investors include Intercontinental Exchange, Founders Fund, General Catalyst, Polychain Capital, D.E. Shaw, G Squared and 1789 Capital. ICE's $1.6 billion is the largest disclosed investment. More: How does Polymarket make money?

Does Polymarket charge to deposit or withdraw?

Polymarket says it charges no fee to deposit or withdraw USDC on Polymarket.com, though intermediaries may charge their own. Polymarket US says withdrawals are free. More: How does Polymarket make money?

Odds and accuracy

How accurate is Polymarket?

Across 1,918 resolved Polymarket markets from 225 of the highest-volume events that closed between 2025-09-25 and 2026-09-21, prices a week before close lined up with what happened: in 9 of 10 price bands the gap between the average price and the share of outcomes that happened is within normal sampling noise (the exception: the 0–10% band, where outcomes happened more often than priced, 3.9% against 1.7%). Outcomes priced at 50% or more a week out happened 75% of the time (246 favourites). The overall Brier score is 0.089, but that is flattered by long shots that were clearly going to lose; on the 613 genuinely uncertain markets (priced 10–90%) it is 0.202, against 0.250 for always saying 50%. More: How accurate is Polymarket?

Is Polymarket more accurate closer to the close?

On the 1,370 markets with a price at all three points, accuracy improves steadily as the close approaches: the Brier score is 0.087 a month before close, 0.063 a week before and 0.046 a day before (lower is better), and favourites won 62%, 82% and 83% of the time. More: How accurate is Polymarket?

Which Polymarket categories are the most accurate?

Among categories with at least 20 genuinely uncertain markets, Politics & Elections markets were the most accurate a week before close (Brier 0.186 on 162 markets priced 10–90%) and Economy & Fed markets the least (0.246 on 23). Some categories have only a few dozen uncertain markets, so read differences of a few hundredths as noise. More: How accurate is Polymarket?

Are high-volume Polymarket markets more accurate?

Within this sample, more trading made no clear difference: on genuinely uncertain markets (priced 10–90% a week out) the quarter with the least volume ($28.1K to $1.05M) scored 0.201 and the quarter with the most ($6.83M and up) scored 0.207. Every market here already traded at least $10,000, so this says nothing about thinly traded markets. More: How accurate is Polymarket?

What does calibration mean for a prediction market?

A calibrated market's 70% outcomes happen about 70% of the time. The table groups outcomes by their price a week before close and shows how often each group actually resolved Yes. More: How accurate is Polymarket?

How was this study done?

We took the highest-volume Polymarket events that closed in the last 12 months, up to 15 of the most-traded outcome markets per event (at least $10,000 traded), read each market's price 7 days before it closed from Polymarket's public price history, and compared it with the final resolution. Markets that resolved 50-50 or had no price history at that time are excluded. More: How accurate is Polymarket?

Is there a favorite-longshot bias on Polymarket?

Not the classic kind. In our sample of 1,918 resolved Polymarket markets, outcomes priced under 10% a week before the close happened 3.9% of the time against an average price of 1.7%, about 2.3 times more often than priced, while outcomes priced 60% or more were priced about right (81% happened at an average price of 81%). The long-shot wins cluster in a few events (48 wins from 36 events), so read it as a pattern in this sample, not a law. More: Is there a favorite-longshot bias on Polymarket?

Should I buy long shots on Polymarket?

No trading conclusion follows from this sample: the wins cluster in a few events, the prices are a week before the close, and fees and spreads are not included. More: Is there a favorite-longshot bias on Polymarket?

How often do Polymarket long shots win?

Outcomes priced under 10% a week before the close happened 3.9% of the time in our sample (48 of 1,243). More: Is there a favorite-longshot bias on Polymarket?

Can a 90% favorite lose on Polymarket?

Yes. A 90% price means the outcome should fail about one time in ten. In our sample of 1,918 resolved Polymarket markets that closed between September 25, 2025 and September 21, 2026, outcomes priced 90% or more a week before the close happened 95% of the time: 3 of 62 lost. Long shots priced 20% or less came through 82 times out of 1,413 (5.8%, against an average price of 3.2%). More: Can a 90% favorite lose?

How often do Polymarket favorites win?

Outcomes priced at 50% or more a week before the close happened 75% of the time in our sample of 1,918 resolved markets. More: Can a 90% favorite lose?

Do long shots ever win?

Yes: 82 of 1,413 outcomes priced 20% or less a week out happened in our sample. More: Can a 90% favorite lose?

Why did a Polymarket price suddenly jump?

Usually because of news, a poll or data release, or a large order hitting a thin order book. If the spread is wider than 10 cents, the displayed price is the last trade, so a single trade can look like a big move. More: What moves Polymarket prices?

Can one trader move Polymarket odds?

In thin markets, yes. Deep markets take much more money: one study estimated that moving Polymarket's Trump price by five points in October 2024 cost about $9.1 million. More: What moves Polymarket prices?

Is Polymarket trading volume real?

Not all of it. Columbia University researchers estimated that wash trading averaged about 25% of Polymarket's volume over three years, so treat volume as a rough guide to activity. More: What moves Polymarket prices?

Why do “by date” markets fall over time?

Each day that passes without the event leaves less time for it to happen, so the Yes price tends to drift down unless news raises the odds. More: What moves Polymarket prices?

What is the biggest Polymarket market ever?

The biggest Polymarket market of all time is World Cup Winner with $4.33B traded, ahead of Presidential Election Winner 2024 ($3.69B) and NBA Champion ($1.71B). The 100 biggest markets together traded $34.26B; the biggest one still open is Democratic Presidential Nominee 2028 ($1.28B). More: Biggest Polymarket markets of all time

How is volume counted?

As the total amount traded over the market's life across all its outcomes, from Polymarket's public data. More: Biggest Polymarket markets of all time

How often is this ranking updated?

Twice a day with the rest of the odds pages. More: Biggest Polymarket markets of all time

How do I convert American odds to a Polymarket price?

Turn the odds into an implied probability — favourites: odds ÷ (odds + 100); underdogs: 100 ÷ (odds + 100) — and read it in cents. −150 is 60%, so the same outcome would trade near 60¢ on Polymarket before fees and the sportsbook margin. More: Sportsbook Odds to Polymarket Price Converter

What is the vig and why remove it?

The vig (or margin) is the bookmaker's built-in edge: both sides of a line add up to more than 100%. Removing it gives the fair probability, which is what to compare with a Polymarket price. More: Sportsbook Odds to Polymarket Price Converter

Are Polymarket odds better than sportsbook odds?

Often closer to fair, because Polymarket charges a small taker fee instead of a margin on both sides — but it varies by market and liquidity. Compare the no-margin probability here with the Polymarket price. More: Sportsbook Odds to Polymarket Price Converter

What is a Kelly criterion calculator?

A Kelly criterion calculator estimates the bankroll fraction to risk when you know your probability estimate and the market odds. It is a sizing tool, not a signal generator: bad probability estimates still create bad bets. More: Kelly Criterion Calculator for Polymarket

How do I use Kelly sizing on Polymarket?

Convert the Polymarket YES price to decimal odds, compare the market probability with your researched probability, enter the edge, and use the fractional Kelly output as a conservative position-size ceiling. More: Kelly Criterion Calculator for Polymarket

Should prediction-market traders use full Kelly?

Usually no. Full Kelly assumes your probability estimate is correct, which is rarely true in live prediction markets. Half Kelly or quarter Kelly reduces volatility and gives room for fees, spread, slippage, and model error. More: Kelly Criterion Calculator for Polymarket

How the different markets work

How do Polymarket awards markets resolve?

On the official announcement by the awarding body, as the rules specify, including how shared or unlisted winners are handled. More: How Polymarket Awards Markets Work (Oscars, Nobel, Ballon d'Or, VMAs)

Why does the favourite sometimes lose on Polymarket?

Prices are probabilities, not certainties: a 60% favourite still loses about four times in ten. More: How Polymarket Awards Markets Work (Oscars, Nobel, Ballon d'Or, VMAs)

What source do Polymarket box office markets use?

The one named in each market's rules — typically a box office tracking site's reported figure for the stated period. More: How Polymarket Box Office Markets Work (Opening Weekend and Total Gross)

Why do box office odds change so much on Friday?

Preview and first-day numbers arrive, and they are strong predictors of the weekend total. More: How Polymarket Box Office Markets Work (Opening Weekend and Total Gross)

What does “Bitcoin above ___ on September 24” mean on Polymarket?

It is a set of yes/no markets, one per price level. Each pays $1 if Bitcoin's price at the time and source named in the rules is above that level. More: How Polymarket Crypto Price Markets Work: “Above X on Date” and “What Price Will It Hit”

How is a “what price will Bitcoin hit” market different?

It resolves Yes for every level the price reaches at any time during the period, whether or not it stays there. More: How Polymarket Crypto Price Markets Work: “Above X on Date” and “What Price Will It Hit”

How do “by date” markets on Polymarket work?

Each deadline is a separate yes/no market that resolves Yes if the event, as defined in the rules, happens on or before that date; otherwise it resolves No when the date passes. More: How Polymarket “By Date” Deadline Markets Work (Will X Happen By …?)

Why is the later deadline always more expensive?

Because it includes every earlier date: if the event happens by September 30, it has also happened by December 31. More: How Polymarket “By Date” Deadline Markets Work (Will X Happen By …?)

What does “beat quarterly earnings” mean on Polymarket?

That the company reports earnings per share above the consensus estimate named in the market's rules, using the EPS measure and source the rules specify. More: How Polymarket Earnings Markets Work (“Will X Beat Quarterly Earnings?”)

When do Polymarket earnings markets resolve?

Soon after the company publishes its quarterly results, based on the figure in its official earnings documents or the fallback source named in the rules. More: How Polymarket Earnings Markets Work (“Will X Beat Quarterly Earnings?”)

Which release decides a Polymarket CPI market?

The one named in the rules — usually the first official release of the stated series — not later revisions. More: How Polymarket Economic Data Markets Work (CPI, Jobs Report, GDP)

Why do the prices jump at 8:30 a.m. Eastern?

Most US data are published at 8:30 a.m. ET; once the number is out, the matching range goes to nearly $1. More: How Polymarket Economic Data Markets Work (CPI, Jobs Report, GDP)

How do Polymarket election markets resolve?

On the result as defined in the rules — typically the certified winner or the call by named sources — with specific handling for recounts and disputes. More: How Polymarket Election Markets Work (Winner, Party Control and Margins)

Are Polymarket election odds a poll?

No. They are prices set by traders risking money; they often move with polls but also react to other news. More: How Polymarket Election Markets Work (Winner, Party Control and Margins)

How do Polymarket Fed decision markets resolve?

On the change to the federal funds target range announced at the named meeting, measured as the rules specify (for example by the upper bound), into the listed buckets such as 25 bp cut, no change or 25 bp hike. More: How Polymarket Fed Decision Markets Work (Rate Cut, Hike or Hold)

Are Polymarket Fed odds the same as CME FedWatch?

They measure the same question from different sources — traders' prices on Polymarket versus fed funds futures — and usually track each other closely, with occasional gaps. More: How Polymarket Fed Decision Markets Work (Rate Cut, Hike or Hold)

How do Polymarket mention markets resolve?

Each listed word resolves Yes if the named speaker says it during the event and in the form defined by the rules, as checked against the source the rules name. More: How Polymarket Mention Markets Work (What Will X Say?)

Do variations of a word count?

Only as the rules allow — some count plurals and possessives, others require the exact word. More: How Polymarket Mention Markets Work (What Will X Say?)

Why do all the outcomes in a Polymarket market add up to 100%?

Because exactly one of them will resolve Yes; each outcome's price is its probability, so the probabilities together cover every possible result (spreads make the sum drift slightly above 100%). More: How Polymarket Multi-Outcome Markets Work (Who Will Win, Which Range)

Can I bet against an outcome instead of for one?

Yes — buy its “No” share, which pays $1 if any other outcome wins. More: How Polymarket Multi-Outcome Markets Work (Who Will Win, Which Range)

How do Polymarket sports markets compare with a sportsbook?

You trade shares against other users instead of betting against a bookmaker, so the price is set by the market and there is no built-in margin on both sides — only the spread and a small taker fee on some markets. More: How Polymarket Sports Game Markets Work (Moneyline, Spread and Totals)

How do Polymarket stock price markets resolve?

Yes if any one-minute candle during regular trading hours in the stated week or month reaches the listed price (the high for upward levels, the low for downward ones), according to the price source in the rules; otherwise No. More: How Polymarket Stock Price Markets Work (“What Will SPY Hit This Week?”)

Do after-hours prices count in Polymarket stock markets?

No. The rules count only prices from the regular trading session of the stock's primary exchange. More: How Polymarket Stock Price Markets Work (“What Will SPY Hit This Week?”)

How do Polymarket temperature markets resolve?

To the temperature range that contains the highest (or lowest) temperature recorded on that date by the station named in the rules, in the unit the rules give. More: How Polymarket Weather Temperature Markets Work (Highest Temperature Today)

Where does the temperature data come from?

From the source named in each market's rules — for example a national weather service's airport station. More: How Polymarket Weather Temperature Markets Work (Highest Temperature Today)

How do Polymarket tweet count markets resolve?

To the range containing the number of qualifying posts made by the account between the start and end times in the rules; the rules also say what counts as a post and how it is tallied. More: How Polymarket Tweet Count Markets Work (Elon Musk # of Posts)

Why do Elon Musk tweet markets have so many outcomes?

Each outcome is a count range; together they cover every possible total, and exactly one resolves Yes. More: How Polymarket Tweet Count Markets Work (Elon Musk # of Posts)

How do Polymarket Up or Down markets resolve?

By comparing two prices from the data source named in the rules — typically the close of a set candle with its open, or with the previous day's close. Up pays $1 if the price finished higher (the rules say how a tie is treated). More: How Polymarket Up or Down Markets Work (15-Minute, Hourly and Daily)

How long do Up or Down markets last?

From a few minutes to a day; each window is its own market, and new ones open continuously. More: How Polymarket Up or Down Markets Work (15-Minute, Hourly and Daily)

What happens when a Polymarket Yes/No market resolves?

Winning shares can be redeemed for $1 each; losing shares are worth nothing. More: How Polymarket Yes/No Markets Work: Prices, Payouts and Resolution

Is buying No the same as selling Yes?

Economically yes: Yes and No together always pay exactly $1, so buying No at 85¢ has the same payoff as selling Yes at 15¢. More: How Polymarket Yes/No Markets Work: Prices, Payouts and Resolution

Is Polymarket more accurate than polls?

It depends on what you compare. Markets beat single polls in long-run studies of the Iowa Electronic Markets, but properly adjusted poll-based forecasts did better in other research, and both have missed. More: Polymarket vs polls: what is the difference?

Why did Polymarket favor Trump in 2024 when polls were tied?

A market prices the chance of winning, not vote share, so a tied polling average can still come with a market favorite. Polymarket had Trump at 56.3% at midday on November 4, 2024, and he won all seven swing states. More: Polymarket vs polls: what is the difference?

Can a poll move Polymarket odds?

Yes. After the final Selzer Iowa poll on November 2, 2024 showed Harris ahead in Iowa, Polymarket's price for a Democratic win there rose from 8.5 cents to 18 cents within minutes; the market later resolved No. More: Polymarket vs polls: what is the difference?

What is a poll's margin of error?

It is the range expected from sampling alone. Pew notes that the margin on the gap between two candidates is roughly twice the margin on each candidate's share, and other errors, such as who turns out to vote, come on top. More: Polymarket vs polls: what is the difference?

Is Polymarket more accurate than CME FedWatch?

There is no settled answer for Polymarket. A Federal Reserve Board staff paper found that the most likely outcome on Kalshi had zero average error by the day of FOMC meetings, an improvement over fed funds futures, but it did not study Polymarket. More: Polymarket vs CME FedWatch: how the Fed odds differ

Why does FedWatch show a different number from Polymarket?

FedWatch converts monthly-average futures prices into odds under a 25-basis-point assumption, while Polymarket traders price each outcome directly and settle on the upper bound of the target range. Timing, fees and who is trading also matter. More: Polymarket vs CME FedWatch: how the Fed odds differ

What does a Polymarket Fed market settle on?

The change in the upper bound of the federal funds target range announced in the FOMC statement for that meeting, with unlisted changes rounded up to the nearest 25 basis points. More: Polymarket vs CME FedWatch: how the Fed odds differ

How can I turn a fed funds futures price into odds myself?

Subtract the price from 100 to get the expected average rate for the month, work out the rate after the meeting from the days before and after it, and divide the implied change by 25 basis points. Our calculator does this. More: Polymarket vs CME FedWatch: how the Fed odds differ

Polymarket compared

What is the difference between Polymarket and Kalshi?

Kalshi is a US exchange regulated by the CFTC and trades in US dollars. Polymarket's main exchange, polymarket.com, is international, settles in the USDC stablecoin and is close-only for US users; Polymarket also launched a separate CFTC-approved US app in December 2025. More: Polymarket vs Kalshi odds today

Why do Polymarket and Kalshi show different odds for the same event?

They have different traders, fees, order books and sometimes different resolution rules. A few points of difference is common; larger gaps usually close as traders move money, but fees, spreads and access rules mean a gap is not free money. More: Polymarket vs Kalshi odds today

Which is cheaper, Polymarket or Kalshi?

For 100 shares bought as a taker at 50¢, Polymarket's 4% politics rate costs $1.00 and Kalshi's general fee $1.75; at 90¢ it is $0.36 versus $0.63. Makers pay nothing on Polymarket; on Kalshi, makers pay a smaller fee on some markets. More: Polymarket vs Kalshi odds today

What is the best Polymarket alternative in the US?

It depends on what you trade. Kalshi and Crypto.com list sports, politics and economics on CFTC-regulated exchanges; ForecastEx suits Interactive Brokers clients aged 21+ and pays an interest-like coupon; PredictIt suits small political positions up to $3,500 per contract; Robinhood and DraftKings route to regulated exchanges from their own apps. US residents can also use Polymarket's own CFTC-regulated app, Polymarket US. More: Polymarket alternatives

Is there a free alternative to Polymarket?

Manifold uses play money called mana, which cannot be cashed out; every new user starts with M1,000. More: Polymarket alternatives

What can I use outside the US?

Polymarket.com works in countries that are not on its blocked list; Betfair Exchange holds licences in the UK, Malta, Italy, Romania and Brazil but bars US customers; Interactive Brokers offers ForecastEx to eligible clients in Canada, Hong Kong, Ireland and Singapore; Kalshi says it supports participation from more than 140 countries; the crypto markets Limitless (on Base) and Myriad (on BNB Chain) bar US users and some other places. More: Polymarket alternatives

Is Robinhood's prediction market the same as Kalshi?

Robinhood routes event contracts to several CFTC-licensed exchanges, including KalshiEX, ForecastEX and Rothera; its prediction markets hub launched on March 17, 2025 with contracts from Kalshi. More: Polymarket vs Robinhood

How do Robinhood fees compare with Polymarket fees?

Robinhood's commission is k x p x (1-p) per contract (k = 10%, or 5% with Gold), capped at $0.01 per contract, plus an exchange fee of up to $0.01 per contract per side. Polymarket US charges takers 0.0695 x contracts x p x (1-p), at most $1.74 per 100 contracts at 50 cents, and pays makers a rebate. More: Polymarket vs Robinhood

Can I trade Robinhood prediction markets in every state?

No. Robinhood says Maryland residents can't trade sports event contracts, Nevada residents can't open new ones since December 1, 2025, and other state restrictions may apply. More: Polymarket vs Robinhood

Is PredictIt or Polymarket better for US traders?

They serve different needs. PredictIt is open to US persons 18 and older, focuses on political and economic questions and caps each contract at $3,500. US residents cannot use Polymarket.com; they use the Polymarket US app, a CFTC-regulated exchange with sports, politics, crypto and more and no trading size limits. More: Polymarket vs PredictIt

How do PredictIt fees compare with Polymarket fees?

PredictIt takes 10% of the profit on shares sold above cost or redeemed at $1, and 3% on card deposits. Polymarket US charges takers 0.0695 x contracts x p x (1-p), at most $1.74 per 100 contracts at 50 cents, and pays makers a rebate; Polymarket.com charges takers shares x rate x p x (1-p) with a rate from 0 to 0.07 by category. More: Polymarket vs PredictIt

Is PredictIt regulated like Polymarket US?

No. PredictIt says it is not regulated by the CFTC and relies on a no-action letter; Polymarket US is a CFTC designated contract market and clearing organization. The international Polymarket.com is not CFTC-regulated either. More: Polymarket vs PredictIt

Does PredictIt report winnings for taxes?

PredictIt issues IRS Form 1099 to US-resident traders with net profit of $600 or more in a calendar year. More: Polymarket vs PredictIt

Can US residents use Betfair Exchange?

No. Betfair's terms list the United States among prohibited territories, along with countries such as Canada, France and Germany. More: Polymarket vs Betfair Exchange

How does Betfair commission compare with Polymarket fees?

Betfair charges commission on net winnings only, 5% to 7% by country, and an Expert Fee of 20% or 40% for its most profitable customers. Polymarket.com charges takers shares x rate x p x (1-p) on each trade, with a rate from 0 to 0.07 by category. More: Polymarket vs Betfair Exchange

Does Betfair have prediction markets?

Its exchange already lists politics and other special markets, and Covers reported in April 2026 that Betfair was beta-testing 'Betfair Predicts', a Yes/No interface for sports, politics and entertainment, with select UK users. More: Polymarket vs Betfair Exchange

Can you arbitrage Polymarket and Kalshi?

Only when the two prices plus fees add up to less than $1 for the same outcome set, the rules match, and you can legally use both platforms — which is rare, because Kalshi serves US residents and polymarket.com is close-only in the US. More: Polymarket Arbitrage Calculator

How are fees included in the calculation?

Polymarket charges takers shares × rate × p × (1 − p) with a category rate; Kalshi's general taker fee is 0.07 × contracts × P × (1 − P), rounded up to the next cent. The calculator adds both to the cost. More: Polymarket Arbitrage Calculator

What is a good arbitrage margin?

Anything above zero after fees is a gross profit, but compare it with the time until settlement: annualize it, and weigh the rule and access risks before trading. More: Polymarket Arbitrage Calculator

Data, citing and tools

Where can I download Polymarket historical data?

The research datasets above are free CSV and JSON files: resolved markets with their prices 30, 7 and 1 days before the close, resolution times and disputes, crypto price strikes, Polymarket vs Kalshi gaps and upsets. More: Free Polymarket data: datasets and API

Is Polymarket data free to use?

The files and the JSON API on this site are free under CC BY 4.0: credit Polymarket View with a link. Polymarket's own website and API have their own terms. More: Free Polymarket data: datasets and API

How often is the data updated?

Live odds endpoints twice a day; the research samples weekly. Each file carries its own collection date. More: Free Polymarket data: datasets and API

How do I cite Polymarket odds in an article?

Give the price as a percentage chance, the date (and time for breaking news), Polymarket as the venue and a link to a dated page, for example: Polymarket View, “Fed rate odds for every upcoming FOMC meeting”, September 25, 2026, https://polymarkettrader.com/odds/fed-rate-odds/ (data: Polymarket, CC BY 4.0). More: How to cite Polymarket odds

Are Polymarket odds a prediction?

They are prices traders pay for an outcome, read as probabilities. They are not forecasts made by Polymarket or by this site. More: How to cite Polymarket odds

Can I reuse numbers from Polymarket View?

Yes. The numbers on our pages and in our JSON API are free to reuse under CC BY 4.0 with a credit to Polymarket View and a link. More: How to cite Polymarket odds

Where can I get historical Polymarket data for backtesting?

Our data page has free CSV and JSON files of resolved markets with prices before the close, resolution times, crypto strikes, Polymarket and Kalshi gaps and the biggest markets; Polymarket's prices-history API returns timestamped prices for any outcome token. More: How to backtest prediction market strategies

What is look-ahead bias in a backtest?

Using information that was not available when the trade would have been made, such as a market's final volume, or its actual close date when it closed early. More: How to backtest prediction market strategies

How do I include fees in a Polymarket backtest?

Charge takers shares × rate × p × (1 − p) at the rate each market actually had; fees arrived in 2026 and apply only to markets created on or after each category's start date. More: How to backtest prediction market strategies

Is a strategy that wins 75% of the time profitable?

Not necessarily. In our example, favorites a week before the close won 74.8% of the time but returned 2.1% before costs and lost money after a 1-cent worse fill and a 0.05 fee. More: How to backtest prediction market strategies

How much do you make on Polymarket if you win?

$1 per share minus what you paid and any fee. 100 shares bought at 40 cents in a market with a 0.04 fee rate cost $40.96 and pay $100, a $59.04 profit. More: How to calculate profit on Polymarket

What is the break-even probability on Polymarket?

Your all-in cost per share, price plus fee plus any slippage, read as a probability. A trade has positive expected value only if you believe the chance is higher than that. More: How to calculate profit on Polymarket

Do I have to wait for the market to resolve to take a profit?

No. You can sell at any time before resolution at the best bid or with a limit order; a market sale pays the taker fee. More: How to calculate profit on Polymarket

Where can I see the newest Polymarket markets?

On Polymarket's New page, which lists recently opened events first, or by sorting its market list by newest. Our new-markets page and its JSON file list the week's new markets, most traded first, without recurring series and single games. More: How to find new Polymarket markets

Can I create my own market on Polymarket?

No. Polymarket lists markets itself; its help center invites suggestions that include a title, a resolution source and evidence of demand. More: How to find new Polymarket markets

Why does a new market's price jump around?

Its order book may be thin, so small orders move the price, and when the spread is wider than 10 cents Polymarket shows the last trade instead of the midpoint. More: How to find new Polymarket markets

Is the end date when a market pays out?

Not necessarily. The end date is when the market becomes eligible for resolution, and it can resolve earlier if the result is known. Settlement takes about two hours after an undisputed proposal, or four to six days in total if disputed. More: How to find new Polymarket markets

Can IMPORTDATA read JSON?

Google documents IMPORTDATA for CSV and TSV files. For this site's JSON endpoints, use a short Apps Script with UrlFetchApp, as shown above. More: How to get Polymarket odds in Google Sheets

How often does IMPORTDATA refresh?

Google says it checks for updates every hour while the spreadsheet is open. Re-entering the formula forces a refresh; reopening the file does not. More: How to get Polymarket odds in Google Sheets

Do I need an API key?

No. The files are static and need no key or sign-up; credit Polymarket View with a link. More: How to get Polymarket odds in Google Sheets

Why does my sheet keep loading data?

Google limits how much traffic import functions can create across the open spreadsheets you created, so remove imports you no longer need or move large ones to a scheduled script. More: How to get Polymarket odds in Google Sheets

What is a good spread on Polymarket?

The narrower the better: a round trip costs the whole spread. When the spread passes 10 cents, Polymarket stops showing the midpoint and shows the last trade, a clear sign of a thin book. More: How to spot a thin Polymarket order book

Why did I pay more than the price shown?

The displayed price is the midpoint, but a buy fills at the ask; a large order also climbs through higher asks, and takers pay a fee in most categories. More: How to spot a thin Polymarket order book

Does high volume mean a market is liquid?

Not necessarily. Volume measures past trading, while liquidity is what the order book offers now; check the depth near the best prices. More: How to spot a thin Polymarket order book

How can I avoid slippage on Polymarket?

Check the depth first, use limit orders and split large orders. A resting limit order pays no taker fee, but it may not fill. More: How to spot a thin Polymarket order book

Where can I see a Polymarket market's price history?

On the market's page on Polymarket, with ranges from one hour to all time; on our market pages as a 30-day chart; and in raw form from Polymarket's prices-history API or our free JSON files. More: How to track Polymarket price history

Does Polymarket have a price history API?

Yes. The CLOB endpoint /prices-history takes an outcome token ID, a time window or interval and a fidelity in minutes, and returns timestamped prices; the Data API has a newer /v2/prices-history endpoint. More: How to track Polymarket price history

How far back does Polymarket price history go?

Polymarket's Data API documentation says its 12-hour and 3-hour series go back to November 18, 2022, while one-minute, five-minute and 30-minute data are kept for at least 7, 60 and 90 days. More: How to track Polymarket price history

Is the price on a chart what I could have traded at?

Not necessarily. Buyers pay the ask and sellers receive the bid, and a price series shows neither the spread nor the depth at that moment. More: How to track Polymarket price history

Polymarket View is independent and not affiliated with Polymarket. Educational information, not financial or legal advice. Guides · How markets work · Glossary · Polymarket odds today