The competition between Polymarket and Kalshi have sucked up most of the oxygen in the prediction market news media and Twittersphere, to the point that ForecastEx and crypto.com are now merely afterthoughts. (Maybe not so much crypto.com after today’s partnership announcement with Underdog).
Kalshi monthly volume is ~$700m, Polymarket is ~$1b. What do you think IBKRs ForecastEx is?
— 0xperp (@0xperp) August 11, 2025
The truth is roughly $5 million. It was remarkable that ~80% of poll respondents, including the author of this article, were completely unaware of ForecastEx’s monthly volume.
Below, we will examine the first full year of ForecastEx, which officially launched on August 1, 2024. With nearly 4 million traders and institutional accounts, ForecastEx was initially expected to be the 800-pound gorilla of prediction markets.
Interactive Brokers v. ForecastEx v. ForecastTrader
Interactive Brokers is one of the largest online brokerages in the world. Here is a brief history of the company from an SEC filing:
Our founder, chairman and chief executive officer, Thomas Peterffy, began the business in 1977 as an individual market maker on the American Stock Exchange. This enterprise was succeeded by our market making business, Timber Hill, which was formed in 1982. Throughout the 1980s and 1990s, we continually improved and refined our pricing model, its inputs and related software technology. In 1990, Timber Hill joined the first fully electronic options exchange, the Deutsche Terminbörse (DTB). By directly connecting Timber Hill’s market making system to the DTB’s matching engine, price and trade reporting facilities, we proved the viability of a fully automated market making system. In 2000, Timber Hill became a primary market maker on the International Securities Exchange (ISE), the first fully electronic options exchange in the United States. By connecting our system to the ISE, just as we have done with many European and Asian exchanges, we maintained continuous quotes for products listed on the ISE, making electronic option trading a viable alternative to open outcry option trading in the United States. Today, Timber Hill is a primary electronic market maker on most major options exchanges and many stock and commodities exchanges worldwide, and Interactive Brokers, which was added to the group in 1993, is a leading provider of electronic brokerage in stocks, options, futures and forex globally.
2006 Prospectus
ForecastEx is a CFTC-registered Designated Contract Market (DCM) and Derivative Clearing Organization (DCO) for Forecast Contracts. It’s owned by Interactive Brokers.
The only qualified Futures Commission Merchants (FCM) offering ForecastEx Forecast Contracts are:
- Interactive Brokers
- Robinhood
IBKR ForecastTrader (aka ForecastTrader) is Interactive Brokers’ platform for trading forecast and events contracts. It offers contracts from:
- ForecastEx
- CME
However, it is important to note the differing mechanics between CME Group products and ForecastEx instruments:
CME Group instruments can be bought and sold and function as normal futures options.
ForecastEx instruments cannot be sold, only bought. To exit or reduce a position, one must buy the opposing Event Contract, and IB will net the opposing positions together automatically.
API Documentation: Event Contracts
Trading Volume in Year 1
ForecastEx is closed to trading on Saturdays, so there were only 312 trading days in its first year. Below, we can see that trading peaked for the 2024 U.S. Presidential election and has otherwise been minimal.
Market Categories
ForecastEx’s Category Tree is missing categories for 33 of the 92 product codes, so the missing categories, subcategories, and subsubcategories were manually added to contracts by matching the existing nomenclature.
Elections were overwhelmingly the most popular contract category, with 2024 U.S. Presidential election contracts accounting for 97.5% of trading on ForecastEx during its first year. This was largely driven by Robinhood offering ForecastEx presidential election contracts to its users.
Comparing to Kalshi Year 1
Comparing ForecastEx with Kalshi varies depending on how we handle the election markets. Including them, ForecastEx outperformed Kalshi years 1, 2, and 3, combined. Excluding election markets, ForecastEx well underperformed Kalshi’s first year, generating less than one-quarter of the volume (8,257,531 to 38,749,075).
Further Exploration
The inability of Interactive Brokers to recruit existing prediction market traders from other platforms or leverage their existing userbase, particularly institutions.
Further Reading
ForecastEx’s Zero-Fee Claims Hide a Ruinous Market Structure
Regulatory Filings
ForecastEx Product Filings
Kalshi Turns 4
Data Sources
ForecastEx Data
Web API Documentation
API Documentation: Event Contracts
Category Tree