Prediction Markets Move Into Sports: Kalshi and Polymarket Are Competing for World Cup and NBA Finals Traders

The Setup

The 2026 FIFA World Cup opened this week, with Team USA scheduled to face Paraguay on Friday, June 12 at 9 p.m. ET at SoFi Stadium in Inglewood, California, according to FantasyLabs. The NBA Finals are simultaneously in progress, with the New York Knicks trailing the San Antonio Spurs 3-1 heading into a potential closeout game, per the New York Post.

Both Kalshi and Polymarket are running new-user promotions tied to both events. Polymarket is offering a $50 trading bonus after a $20 deposit. Kalshi is offering a $10 bonus after $10 in trades. Multiple outlets — the New York Post, Fox Sports, FantasyLabs, and Mile High Sports — are running affiliate content promoting these offers under various promo codes.

What These Platforms Actually Are

Kalshi and Polymarket are not sportsbooks. They are prediction markets, also called event-contract markets. Users buy and sell contracts priced between zero and one dollar that pay out based on whether a specific outcome occurs.

Kalshi is registered as a Designated Contract Market with the Commodity Futures Trading Commission (CFTC). Polymarket operates as a CFTC-regulated prediction market as well. That regulatory classification allows them to operate in states like California where sports betting through DraftKings or FanDuel remains illegal.

As FantasyLabs noted, California has no legal sports betting, yet Polymarket, Kalshi, and FanDuel Predicts are all available there because they operate under federal commodities law rather than state gambling statutes.

The Market Odds

According to Fox Sports and Polymarket data as of June 11-12, Spain leads the World Cup winner market at 17.2%, France sits at 16.1%, England at 10.8%, and Argentina at 8.7%. The United States and Mexico are each at 1.7%.

For USA vs. Paraguay specifically, Mile High Sports reported Polymarket odds of 45.5% for a U.S. win, 29.8% for a draw, and 24.7% for a Paraguay win as of June 12.

In the NBA Finals MVP market, Kalshi has Knicks guard Jalen Brunson at 51% and forward OG Anunoby at 32%, per the New York Post. Spurs center Victor Wembanyama sits at 17% despite what the Post described as a dominant two-way performance in the series.

The Legitimate Concern

Critics of prediction markets in this context make a fair point: the practical experience of using Kalshi or Polymarket to trade on a game outcome is functionally indistinguishable from placing a sports bet. You pick a team, put money down, and collect if you're right. The contracts, the interface, and the marketing are all sports-adjacent.

The CFTC itself has faced legal battles over whether sports-event contracts fall within its jurisdiction. In 2023, the CFTC attempted to block Kalshi from listing political event contracts before losing that fight in federal court. The question of whether sports contracts are legitimate commodities or rebranded gambling is unresolved, and state attorneys general in several jurisdictions have raised it.

The federal courts and the CFTC's own regulatory framework have allowed these platforms to operate, but the legal line is genuinely contested, not settled.

The Affiliate Promotion Angle

All five source articles reviewed for this piece are affiliate marketing content. The New York Post, Fox Sports, FantasyLabs, and Mile High Sports each carry disclosure language noting they may be compensated if readers sign up. Fox Sports explicitly states: "This page may contain affiliate links to legal sports betting partners. If you sign up or place a wager, FOX Sports may be compensated."

That is standard practice and legally disclosed. But readers should understand they are reading promotional content, not independent analysis. None of these articles examine Kalshi's or Polymarket's fee structures, liquidity risks, or the possibility that a new user trading $10 or $20 in a thin market may receive unfavorable pricing on their contracts.

Availability

Kalshi is available in 42 states, excluded from Arizona, Illinois, Massachusetts, Maryland, Michigan, Montana, Nevada, and Ohio, according to Fox Sports. Polymarket is available in all U.S. states and D.C. except those same eight states plus New Jersey, per Fox Sports.

No investigation or enforcement action against either platform has been announced in any of those excluded states as of June 12, 2026. The exclusions appear to reflect voluntary compliance decisions by the platforms, not active regulatory orders.

The Unresolved Question

The CFTC is currently operating under a Trump-appointed leadership structure that has generally been more permissive toward novel financial products. If that regulatory posture changes, or if a state with a strong gaming-commission lobby challenges these platforms' legal classification in federal court, the availability map for Kalshi and Polymarket could shift substantially before the World Cup knockout rounds even begin.