Midterm trading totals obscure the costs that shape election payouts

Election-night trading volume is not a measure of how much traders lost. According to SiliconSnark, headline midterm figures capture trading activity, with positions potentially changing hands repeatedly rather than representing a single pool of money wagered and lost.

Settlement timing adds another distinction: not every contract reaches its final outcome on election night. The volume recorded during that period therefore cannot, by itself, establish traders’ realized results.

Fees change the payout calculation

SiliconSnark illustrates the cost of trading with a Kalshi example: buying 1,000 contracts at 50 cents incurs a $17.50 trading fee under the platform’s published formula. That charge is separate from the contract purchase price and must be included when assessing the trade’s result.

For Polymarket’s international politics markets, SiliconSnark identifies a listed taker-fee parameter of 0.04. That parameter and Kalshi’s dollar-denominated example are different kinds of figures, not directly comparable charges for the same transaction.

What it means for prediction markets

• Volume is an activity metric: repeated transfers of positions prevent headline turnover from serving as a proxy for trader losses.
• Settlement matters: contracts that remain unresolved on election night limit what that night’s figures reveal about final results.
• Costs need separate accounting: fees affect net outcomes, and comparisons require attention to the applicable platform formula rather than headline parameters alone.