Polymarket's 2026 World Cup winner market has drawn over $2.5 billion in volume, and the big bets are rolling in. One trader pocketed $9.24 million in a single day by correctly calling four match outcomes — including a $7.34 million return on a $7.03 million bet that Iran would not beat New Zealand. Another trader, going by fishalive, turned roughly $427,000 into $4.7 million after Spain drew 0-0 with Cape Verde at 9% odds. A third account, gardenshed, earned $764,000 over four days with a 7-of-8 win rate (87.5%).
The big loss
It's not all wins. One trader lost about $1.2 million on Polymarket betting that Argentina would not beat Algeria. Argentina won 3-0. On Kalshi, a user lost $391,536 on the same Argentina vs. Algeria outcome. But another bettor on Kalshi made $416,184 by wagering $373,407 that Algeria would not win — a play that worked.
Who's favored
France leads Polymarket's winner market at 18%, followed by Spain at 13% and Argentina at 11%. On Kalshi, France sits at 18.7%, Spain at 13.3%, and Portugal at 10.9%. Both platforms let users trade yes-or-no shares on real-world outcomes, with Polymarket being crypto-based. The volume suggests these prediction markets are attracting whale-sized action during the tournament.
With the group stage still in full swing, more lopsided bets are bound to hit — or miss. The next round of matches could swing millions in either direction, and the odds will shift fast as results come in. Both Polymarket and Kalshi are likely to see even more volume as the knockout phase approaches.
