Polymarket · polymarket.com · Direct same-category competitor: both operate prediction markets where users buy and sell binary event contracts on real-world outcomes; Kalshi and Polymarket are explicitly named together in WSJ reporting on ~$20B valuation targets, and talent flows directly...[10][22]

Robinhood · robinhood.com · Sacra independently identified Robinhood as a direct threat to Kalshi's retail prediction market flow, naming the same retail buyer and event-contract product category as the overlap.[21]

Smarkets · smarkets.com · Listed as a Polymarket competitor in the evidence ledger's competitor field, and operates the same central-limit-order-book event-outcome trading model that Kalshi uses; both target traders who want to take positions on political and sports event outcomes.[10]

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