College football accounted for $790 million of notional prediction market trading volume over four days of the NCAA’s Week 1.
Key Takeaways
- Kalshi set a new single-day trading record on Saturday.
- NCAA football produced over $318 million in volume on the busiest day.
- Georgia Tech-Colorado generated $53.7 million on Thursday.
Kalshi’s total volume reached $2.29 billion on Saturday, with $2.02 billion coming from sports and combos, per Aldrin Research. That gave the prediction market operator a new all-time single-day record.
Nearly $250 million – around 11% of Kalshi’s total volume that day – came from college football, a nearly 300% increase from the Week 1 Saturday in 2025. At that time, prediction sites’ market offerings and reach were limited compared to this football season.
Around 80% of the total volume generated by prediction markets from Thursday through Sunday came from sports and combos. College football’s Week 1 wraps up Monday night with Florida State vs. SMU.
Pulling ahead
Kalshi’s $7.3 billion in notional volume during the four days accounted for 86.6% of the trading, including a prediction-market-leading $582.1 million on college football. Polymarket was second in overall college football volume with $58.7 million Thursday through Sunday.
Polymarket’s volume was halted by an unexpected shutdown during much of Saturday’s college football slate. Deposit and trade capabilities were down for several hours.
Polymarket went from accounting for 16.8% of Thursday’s trading and 19.1% on Friday to just 4.6% on Saturday. Despite resolving the issue in plenty of time for Sunday’s handful of college football games, Polymarket made up just 2.1% of the day’s volume.
Most popular NCAA games
Saturday’s NCAA games dominated all prediction market trading from Thursday to Sunday. The sport produced $318.6 million in volume, 95% more than Friday’s MLB slate.
Kalshi dominated the competition with more than 78% of the volume.
The highest-volume game in Week 1, excluding Monday night’s contest, was Georgia Tech-Colorado, the marquee Thursday night showdown. That game generated $53.7 million in volume. The biggest game of Week 1 2025, Notre Dame-Miami, produced $20 million.
Seven college football games this year surpassed that figure alone. Boise State-Oregon produced the highest volume on Saturday, reaching $37.1 million. Kalshi accounted for 88% of the game’s total volume.
Clemson-LSU was second at $35.9 million, while Baylor-Auburn and Western Michigan-Michigan surpassed $20 million each.
The latter came with controversy for Kalshi, which paid out Western Michigan winners before the market was officially settled. The game’s referees put one second back on the clock, leading to a Michigan Hail Mary touchdown pass that resulted in a 13-12 Wolverines’ victory. Kalshi had to go back and reimburse Michigan traders.
Friday’s San Jose State-EMU and Thursday’s UMass-Rutgers games also reached $20 million in volume.
Other operator highlights
Polymarket’s platform issues helped DraftKings Predictions rise to second on Saturday, accounting for $21.1 million, or 6.6%, of the day’s total college football volume. Novig wasn’t far behind with 6.3%, while Polymarket and Crypto.com (2.2%) rounded out the top five for the day.
On a Sunday with a handful of games that produced just $8.2 million in college football, Novig dominated volume with 75%. Kalshi owned 19.7%.
DraftKings took third place behind Kalshi and Polymarket on Thursday, generating $7.7 million, or 5.7% of college football’s $135-million volume for the first day of Week 1. Novig was fourth with 3.5% of the volume, just slightly ahead of Crypto.
Kalshi owned 69.9% of Friday’s $111 million in college football volume. Novig was third behind Polymarket with 4.3%, ahead of DraftKings Predictions’ 3.5%.
Underdog, which shut down its fantasy contests in seven games this week, accounted for around 1% of all volume during the four-day stretch.
Underdog CEO says seven states “have taken a legal viewpoint we disagree with: if we offer our CFTC-licensed products we cannot offer fantasy sports in those states.”
— Geoff Zochodne (@GeoffZochodne) September 5, 2026
So, fantasy shutting down in those jurisdictions, while prediction markets remain. https://t.co/jSaODaFFtm
MLB and tennis, which is featuring the U.S. Open right now, were the only two sports to rank above college football at any point Thursday through Sunday, but none came close to Saturday’s NCAA slate.
