A block trade is a large trade between two eligible parties that is reported to Kalshi under Kalshi's block trade rules.
Who can place a block trade
Both parties to a block trade must be Eligible Contract Participants (ECPs), as defined in the Commodity Exchange Act. A block trade can only be placed on behalf of a customer if that customer specifically directed the order to be executed as a block trade.
Product eligibility
Kalshi designates which products are eligible for block trades. Currently eligible products include all listed markets.
Minimum trade size
The current minimum size is 25,000 contracts. Separate orders cannot be aggregated to reach this minimum.
Pricing
The execution price must be fair and reasonable given the trade's size, available market data in associated markets, and the circumstances of the markets and the parties.
Mandatory reporting window
Blocks must be reported through Kalshi's interface within 15 minutes of the time both parties agree to the trade in principle. The report includes the contract, price, quantity, the respective clearing members, and the time of execution. Kalshi publishes block trades separately from regular-market transactions.