IBKR ForecastEx: what it exposes, how it authenticates, where it stops

What the API exposes

IB models each event contract as an option on an artificial underlying index that groups related contracts. Discovery follows an options-style workflow: categories and markets, contracts within a market, then the conids of the YES and NO legs. The same instruments appear in IB's ForecastTrader UI.

Live data comes from GET https://api.ibkr.com/v1/api/iserver/marketdata/snapshot with a list of conids and field tags (31 last, 84 bid, 85 ask size, 86 ask, 88 bid size, 7059 last size) or as a WebSocket stream. History uses /iserver/marketdata/history in OHLC bars and is only available while a contract is trading; it disappears at expiry. Underlying data sets, such as the official NOAA series behind temperature contracts, are retrievable as historical data.

Orders go through the normal order endpoints and report status and executions over the standard rails. The TWS API documentation has its own ForecastEx Forecast Contracts section with a contract example, market data and an order example.

Authentication and rate limits

Authentication is whatever your IBKR API session uses: Web API session or a TWS or Gateway connection. The event-contract guide adds no separate credential.

The guide publishes no event-contract-specific rate limits; IBKR's general Web API and TWS API limits apply.

Pricing and access

You need an Interactive Brokers account. ForecastEx charges a transaction fee of $0.01 per contract to each side at execution, prices contracts between $0.01 and $0.99, and passes 100% of the interest earned on collateral back to members monthly as an Incentive Coupon.

Contracts are listed with weekly, monthly, quarterly and yearly expiries on topics such as Fed funds targets, unemployment and climate readings.

Where it falls short

ForecastEx contracts cannot be sold. You exit by buying the opposite contract at the same strike, and IB nets the positions automatically, emitting a Bought report followed by Netting reports (side N) within milliseconds. Your position logic has to model that.

The setup is the heaviest here: an IBKR account, an options-shaped discovery chain to reach a conid, and market data that vanishes once a contract expires.

The guide's worked examples use 2024 conids, so expect to rediscover instruments rather than copy them.

Who should use it

Existing IBKR API users adding macro and climate event contracts to a portfolio, and anyone who values the Incentive Coupon on idle collateral.

If you do not already run TWS or the Web API, a native venue API will get you trading faster.