Kalshi’s $100 Million “Combos” Ignite a Parlay Race With Polymarket in U.S. Sports Betting
Kalshi revealed its new “Combos” product for multi-leg sports bets hit over $100 million in trading volume in just one week—a rare peek into the rapid growth of prediction markets in sports. Parlays, which pay out only if every leg wins, made up 63% of New Jersey’s online sports betting revenue through October. Both Kalshi and competitor Polymarket are racing to roll out similar offerings. Polymarket has dangled a $50 bonus for its first multi-leg bet launch. Meanwhile, DraftKings and Flutter’s FanDuel have launched prediction products in states where online sports betting remains banned, though execs remain skeptical that exchanges can rival sportsbooks’ “breadth of choice,” often dismissing them as “structurally limited.” Bank of America analysts estimated back in November that prediction markets now account for 3% to 8% of the legal U.S. online sports betting market — still small, but no longer on the sidelines. Adam Rivers, a managing director at Alvarez & Marsal, pointed to the absence of “the same range of exotic bets” seen at sportsbooks, highlighting “same-game parlays” as a key gap. Shaun Kelley from BofA has dubbed parlays the industry’s “killer app,” yet exchanges face the challenge of building enough liquidity for each leg and