U.S.-Regulated Prediction Exchanges Took 89% of Q3 Volume

U.S.-regulated prediction-market exchanges captured 89% of notional trading volume in the third quarter of 2026, up from 69% in the second quarter, according to quarter-over-quarter volume data. The shift coincided with parlays — contracts that combine several outcomes — becoming the largest U.S. contract category.

The concentration figure deserves a caveat. Notional volume values contracts at payout rather than purchase cost, so it differs from the money traders actually paid. The measure can inflate apparent activity relative to cash-flows on the same platforms.

Which contract types drove the volume?

Parlays accounted for 44% of U.S. notional volume in the quarter. Contracts on individual sports events made up 39%, placing them second. In plain words, multi-leg bundled bets now outdraw single-event sports contracts on these venues.

That mix matters for regulators. Parlays resemble accumulator products familiar from sportsbooks, and their dominance blurs the operational boundary between exchange-traded prediction markets and conventional gambling. The report does not say whether these combined contracts draw retail users into longer odds, a question state regulators have raised elsewhere.

Where does the deposit money come from?

Card-deposit data showed a different pattern from the headline volume figure. In September, 55% of Kalshi's card deposits came from eleven states without legal sports betting. Those states hold roughly one-third of the U.S. adult population.

For Kalshi, prediction markets appear to function as a substitute for wagering in states that have not licensed it. That is a business opportunity and a political liability at once; legislators in non-betting states may read the 55% figure as an arbitrage of their own restrictions. The data does not establish whether those depositors would otherwise have bet illegally or simply not bet at all.

Deposits tied to people aged 18 to 24 represented 30% of Kalshi's card deposits in the observed data. That share sits above what most state-licensed sportsbooks would tolerate, since many set minimum ages of 21, and it invites scrutiny of age-gating on exchanges operating under federal rather than state gambling rules.

Across eight tracked betting and prediction-market apps, Kalshi and Polymarket US together received 11% of card deposits, up from 3% in the first quarter — a near-quadrupling in two quarters. Kalshi's share of U.S. prediction-market search demand rose to 34% from 23% in the prior quarter. Search interest is a demand proxy, not a transaction record, and it may lag or lead actual volumes.

What does the funding pattern signal?

The gap between where volume concentrates and where deposits originate suggests the regulated venues are pulling demand from both legal and unserved markets. The card data covers observed deposits only, and the report does not disclose its sample size or collection method — a limitation worth holding against any firm conclusions about population-wide behavior.

The operational consequence is straightforward: exchanges now process a portfolio that looks increasingly like a sportsbook while operating outside state gambling frameworks. Whether state legislatures in the eleven no-betting states respond with restrictions, or Congress moves on market structure, is the question that will shape this sector's fourth quarter.