What ForecastEx is
ForecastEx is a prediction market exchange operated by Interactive Brokers Group, trading since August 1, 2024. It holds two CFTC registrations at once, Designated Contract Market and Derivatives Clearing Organization, so it runs both the exchange and the clearinghouse (pm.wiki, fetched August 17, 2026).
You reach it through IBKR ForecastTrader, the front end inside an Interactive Brokers account. Some traders reach it without knowing it: Robinhood's prediction markets hub routes part of its contract lineup to ForecastEx.
The pedigree is the pitch. The firm that clears equities and futures for professionals built a regulated venue for event contracts. IBKR rails, CFTC rules.
The mechanism is different. No sell orders
ForecastEx does not run a conventional order book. There are no sell orders. You bid for Yes or you bid for No, and when a Yes bid and a No bid add up to $1.01, they match and a contract exists.
The extra cent is the fee. One cent per contract, flat, and Interactive Brokers adds no commission on top (Market Math, fetched August 17, 2026).
Contracts pay exactly $1.00 on the side that happens and expire at zero on the side that does not. Maximum loss is what you paid. Maximum gain is the distance to a dollar.
A 60 cent Yes bid is a 60 percent implied probability. Same read as every other prediction market, different plumbing underneath.
The incentive coupon is the genuinely new idea
Cash parked in a prediction market position usually earns nothing. ForecastEx passes 100 percent of the interest earned on the collateral behind its markets back to traders as an incentive coupon, quoted around 3.80% APY as of March 2026. It accrues daily on closing position values and pays monthly.
On a long-dated position, that changes the math. A contract that resolves eight months out earns yield the entire time it waits.
Elections a year away, inflation prints, hurricane season. For slow forecasts, the coupon is real money on top of the trade.
The catch. Depth and catalog
ForecastEx lists four categories: economics and policy, politics, climate and weather, and NFL moneylines, the last added in late 2025. Kalshi and Polymarket list thousands of markets across politics, sports, culture, crypto, and more.
The books run thinner too. Reviewers describe a focused selection with moderate depth, and the structure explains it: fewer participants, no market maker crowd, and a bid matching mechanism built for patience rather than speed.
Price a large order into a thin book and the book moves against you. Active traders feel that on the first fill. On liquid events, the same contract usually trades deeper on Kalshi or Polymarket. The 2026 sports-only entrants face the same depth test, measured in the ProphetX review.
ForecastEx vs Kalshi vs Polymarket
Kalshi is the dominant regulated US exchange, clearing $31.5 billion to $33 billion notional in June 2026. Polymarket is the largest book in the world, at $10.6 billion notional in March 2026, with the broadest market set. The head to head between those two is in Kalshi vs Polymarket, and the full platform read on the bigger crypto-native venue is in the Polymarket review.
ForecastEx is the smallest of the three by a wide margin, and the only one that pays interest on your positions while charging a flat penny.
Different tools for different jobs. ForecastEx suits slow, rate-bearing macro positions on IBKR rails. Kalshi and Polymarket carry everything that needs depth and speed. For the wider field beyond these three, see Polymarket alternatives.
How serious traders fit ForecastEx in
Kairos is a professional terminal for prediction markets. It unifies Kalshi, Polymarket, and Predict.fun into one book: sub-second data, a global best bid and best ask, advanced order types, low latency execution.
ForecastEx sits outside that book, and for the way it trades, that is fine. Park the slow macro positions there and collect the coupon. Trade everything that moves on the deep venues, through a terminal built for it.
A yield-bearing venue for forecasts. Kairos for trading.
- Choose ForecastEx if you hold long-dated economic or climate positions and want interest on the collateral while you wait.
- Choose Kalshi or Polymarket if the trade needs depth, speed, or a market the ForecastEx catalog does not carry.
- Choose Kairos if you trade prediction markets seriously and want the deep venues in one terminal.