Kalshi Hits Record $19 Billion Week As Polymarket US Triples Fall Trade Volume

Kalshi 's weekly contract volume climbed to $19.03 billion for Oct. 5-11, 2026, the highest of the six weekly totals reviewed. Polymarket US rebounded to 2.82 billion in reported Trade Volume, while Polymarket recorded $498.81 million in cash-dollar volume. Weekend trading accounted for a large share of activity. Kalshi's contract volume rose across the six-week series, while Polymarket US recovered from the previous week's decline. The venue-wide totals don't show how much of the increase came from NFL or college football. Kalshi recorded $19.03 billion in weekly contract volume from Oct. 5-11, up 3.57% from the previous week .