Polymarket regains top weekly trading volume from Kalshi

Weekly trading volume across online prediction markets topped $2 billion last week as Polymarket regained the top spot from rival Kalshi, reflecting a surge in user activity and fresh institutional backing that is reshaping the sector. Data compiled by Dune Analytics show Polymarket accounted for roughly $1 billion in volume while Kalshi recorded about $950 million during the week, with sports markets generating $414.7 million and politics-related markets $322.6 million.

Polymarket had trailed Kalshi for eight weeks after Kalshi's user activity jumped in August with the start of the NFL season. Polymarket began beta testing a U.S. app just over a week ago and increased trading in the run-up to November elections, enabling it to retake the lead. Smaller platforms have also expanded: Limitless’s weekly volume rose to about $21.9 million and Myriad to roughly $3.8 million.

The sector’s growth has coincided with a notably more permissive federal regulatory posture. Both Kalshi and Polymarket received no-action letters from the Commodity Futures Trading Commission earlier this year, clearing the way for broader U.S. participation without immediate threat of federal enforcement. A...