Home › Polymarket vs ForecastEx (Interactive Brokers)
Facts checked September 24, 2026 against each platform's own pages, filings and news reports · numbered sources below
ForecastEx is Interactive Brokers' own CFTC-regulated exchange: contracts cost $0.01 to $0.99, pay $1, carry a $0.01 fee per side and earn an interest-like coupon, 3.38% APY according to IBKR [1][2][3][4]. It is open to eligible IBKR clients aged 21 and over in several countries [4]; Polymarket runs Polymarket.com internationally and Polymarket US for US residents [5][6].
| Polymarket | ForecastEx (Interactive Brokers) | |
|---|---|---|
| Who runs it | Two products: the international Polymarket.com, and Polymarket US, operated by QCX LLC [7][8] | ForecastEx LLC, a wholly owned Interactive Brokers subsidiary based in Chicago [1][19] |
| Regulation | Polymarket.com says it is not regulated by the CFTC; Polymarket US is a CFTC designated contract market and clearing organization [7][6] | CFTC designated contract market and derivatives clearing organization since June 2024 [1] |
| Who can use it | Polymarket.com is blocked in 39 countries, including the US, UK, France and Germany; US residents use the separate Polymarket US app (18+, identity check) [9][5][8] | Eligible clients aged 21+ of Interactive Brokers LLC, Canada, Hong Kong, Ireland and Singapore; US election contracts for eligible US residents only [4] |
| Money | Polymarket.com: pUSD, a token backed 1:1 by USDC on Polygon; Polymarket US: US dollars [10][6] | Your Interactive Brokers account; contracts trade from $0.01 to $0.99 and pay $1.00 if right [2][4] |
| Trading fees | Polymarket.com: takers pay shares x rate x p x (1-p), with a rate from 0 (geopolitics) to 0.07 (crypto); Polymarket US: takers pay 0.0695 x contracts x p x (1-p) and makers get a rebate [11][12] | $0.01 per contract charged to each side, with no IBKR commission on ForecastEx contracts; positions earn an incentive coupon, 3.38% APY according to IBKR [3][20][4] |
| Deposits and withdrawals | Polymarket.com: crypto deposits from several chains, no Polymarket fee; Polymarket US: card or ACH up to $50,000 a day, wire from $1,000, free withdrawals [13][11][14][15] | Through the Interactive Brokers brokerage account [4] |
| Limits | Polymarket US sets no trading size limits [16] | Position accountability level of 250,000 contracts in any one market [21] |
| Markets | Politics, sports, crypto, economics, culture, weather, tech and more [6][11] | Economics, elections, government and climate; since May 2026 IBKR also routes Kalshi and CME contracts from the same screen [3][22] |
| How markets settle | Polymarket.com: UMA optimistic oracle with a 2-hour challenge window and a UMA vote on disputes; Polymarket US: the exchange applies each market's listed sources [17][18] | From source agencies such as the BLS, Census Bureau, BEA, NOAA and the University of Michigan; an Event Review Committee decides disputes [2][21] |
All current prices: Polymarket odds today · fees on a real order: Polymarket fee calculator · where Polymarket is available
Yes: an incentive coupon, 3.38% APY according to Interactive Brokers, accrues daily on the closing market value of positions and is paid monthly. [4]
Since May 14, 2026 IBKR's Prediction Markets interface lets eligible clients trade Kalshi, CME Group and ForecastEx contracts from one account, routing to the best net price. [22]
ForecastEx charges $0.01 per contract to each 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. [3][12]
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