Crypto-related contracts on prediction platforms Kalshi and Polymarket reached a record $2.7 billion in weekly notional volume, with the majority of activity focused on short-term bets on bitcoin and other cryptocurrency price movements. Crypto now ranks as the second-most-traded category on both platforms, trailing only sports.
Bitcoin traded within a narrow range of approximately $80,000 to $84,000 during the week, creating conditions that rewarded rapid trading strategies.
15-Minute Markets Drive Growth
Short-duration contract markets are commanding the bulk of activity. On Kalshi, crypto volume totaled approximately $8.17 billion between September 1 and 28, with roughly $7 billion—or 86%—generated from 15-minute markets. Crypto's share of Kalshi's total platform volume jumped from 2.6% before the format launched to 14.5% in September.
Polymarket's U.S. platform saw even faster expansion. Its 15-minute bitcoin markets generated $91.76 million in their first full week, from September 23 to 29. Daily volume climbed from $2.40 million to $27.71 million, while reported transactions grew from 63,650 to 739,034 over the same period.
For users, these contracts function as a simplified, capped-risk alternative to leveraged trading where losses are limited and liquidation is not possible.
Broader Platform Integration
Major cryptocurrency platforms are expanding access to prediction markets. Coinbase's prediction market offering is powered by Kalshi, while wallet provider Phantom has begun a staged U.S. rollout of in-wallet markets. Phantom's contracts are priced at $0.02 each, with fees split between Phantom and Kalshi plus a small network fee.
Legal and Regulatory Headwinds
Growth may face obstacles ahead. Legal challenges against sports contracts in several U.S. states could make crypto exchanges more cautious about prediction market expansion. The Pentagon recently banned military personnel from trading on Polymarket and Kalshi following a $400,000 betting scandal.
Longer-dated contracts show more cautious sentiment. On options platform Derive, the implied probability of bitcoin reaching $100,000 by Christmas rose from 9.7% to 12% during the week, even as spot bitcoin ETFs experienced outflows of $635.6 million on Thursday.
