Polymarket keeps lead in US prediction-market search as Kalshi narrows gap

Polymarket held the largest share of branded search demand among US prediction markets from January to August 2026, even as Kalshi cut the gap and far outpaced it in trading, according to analytics firm Blask.

What happened

Blask measured search interest with its Brand's Accumulated Power (BAP) metric, which divides branded search demand between competing names. Polymarket's BAP dropped 16.56 percentage points between January and August, from 74.3% to 57.8%. Kalshi's share rose from 23.1% to 35.8%, a gain of 12.7 points. Together the two fell from 97.4% to 93.6%. Among smaller competitors, Novig posted the fastest rise in Blask Index from January to July, at 64.9%.

During the World Cup, Kalshi's BAP was 18% in May, 29% in June and 36% in July, while Polymarket slid from 80% to 69% and then 61%. Kalshi's Blask Index also grew 22.8% from January to July while the overall prediction-market segment shrank 22%. That suggests Kalshi drew more search interest in absolute terms, not merely a larger slice of a shrinking pool.

Trading figures point the other way. The Block data put Kalshi's August volume at $37.17 billion, compared with a combined $8.16 billion for Polymarket and Polymarket US. For July, Pew Research Center, working from The Block's numbers, counted nearly $53 billion across the two firms: roughly $40.1 billion for Kalshi and about $12.9 billion for the Polymarket venues together.

Estimates for the World Cup itself vary. Reuters reported about $27 billion in Kalshi volume during the tournament, while TickerTracker counted about $13.8 billion across its individual World Cup markets, leaving out combo markets.

The biggest search day of 2026 was not during the tournament. Blask's Index reached its highest point on 2 March, one day ahead of the first midterm primaries in Texas, North Carolina and Arkansas, at over four times the baseline from mid-May. Super Bowl Sunday exceeded that baseline by more than three times, and the top World Cup reading reached about half the March level. Blask said the link to the primaries is an inference from timing, not proof from query-level data.

The World Cup did lift search more steadily. Over the six weeks, median daily prediction-market Index levels stood 38% higher than in the four weeks leading up to kickoff, while Blask's measure of traditional US iGaming was 2% lower.

Why it matters

Blask stressed that the two datasets answer different questions. In its words, "Trading volume is a liquidity/execution metric; BAP is an attention metric." It attributes Polymarket's search lead largely to name recognition, as the more established and more globally covered brand. It also noted that DraftKings and FanDuel register little prediction-market-specific BAP despite big sportsbook recognition, because Blask isolates prediction-market searches for multi-product operators.

The gap between search and volume may also reflect where users are in the customer journey. Blask suggested much World Cup trading came from people who were already active and had no need to search again. Mobile data shows new users arriving too: Sensor Tower found Kalshi's average weekly downloads in the tournament's first three weeks were nearly double its Super Bowl LX level, and Polymarket's were nearly four times higher. Apptopia also reported rising daily active users for prediction-market apps while sportsbook app growth began to retreat.

Newcomers may discover these platforms via app stores, ads, referrals or social channels, with no branded web search involved. Installed users can keep trading without searching again, and some searchers never trade.

What's next

In its own tests of traditional iGaming, Blask reports a 95% correlation linking search share to market performance. It has not yet run the same test for prediction markets, and it said it is not claiming an answer either way. Until it does, the search data is best read as a gauge of attention, not a stand-in for trading volume or market share.