- ▸ Kalshi hit $3.54B (+21.8% WoW) and Polymarket $2.48B (+25.5%), combining for $6.02B and pushing total industry volume to an ATH $6.5B.
- ▸ The 2026 Masters tournament breaks records for Kalshi, with $545 million traded
- ▸ Kalshi sports hit 85.8% of volume ($3.04B) on Masters spike, while Polymarket’s Trump + Politics surged to $842.5M (34% share).
The week of April 6–11 was the strongest yet for prediction markets, driven by The Masters and a combination of US election races and geopolitical events. Kalshi posted an all-time best $3.54B in notional volume (+21.8% week-over-week), while Polymarket surged to $2.48B (+25.5% WoW).
The two industry leaders combined for $6.02B for the week, based on our tracking, just edging out its previous all-time high combined $5.94B March 16 week during peak March Madness action. Together with other tracked platforms, the industry crossed $6.5B in combined notional volume, also a new overall high.
Three storylines drove the week. The Masters Tournament was the headlining sports event, with Kalshi setting a new tentpole record of $545 million.
Polymarket’s Trump and Politics categories exploded, seeing +141% and +58.7% WoW lifts respectively, fueled by US–Iran conflict markets and continued 2028 presidential election positioning.
Kalshi vs. Polymarket 6-Week Trend (March 3-April 11)
| Week | Kalshi Volume ($) | Polymarket Volume ($) | Kalshi Transactions | Polymarket Transactions |
|---|---|---|---|---|
| 2026-03-02 | $2.86B | $2.50B | 20.0M | 26.3M |
| 2026-03-09 | $2.93B | $2.34B | 19.7M | 24.7M |
| 2026-03-16 | $3.40B | $2.54B | 21.4M | 27.4M |
| 2026-03-23 | $2.73B | $2.24B | 19.0M | 26.3M |
| 2026-03-30 | $2.90B | $1.97B | 20.1M | 22.7M |
| 2026-04-06 | $3.54B | $2.48B | 22.2M | 22.3M |
Kalshi sets new record as Masters drives sports to 85.8% of volume
Kalshi’s volume rebounded sharply from the post-Final Four cooldown, reaching $3.54B, its strongest week since the peak of March Madness. Kalshi’s Masters Tournament Champion market was the platform’s top market for the week. The main Masters champion market alone attracted $460.3M in notional trading volume, not including many other popular Masters markets like specific round winners. Sports and Exotics combined accounted for 85.8% of the total sports volume.
Kalshi’s +10.2% transaction growth lagged its +21.8% volume gain, meaning average trade size grew ~10% to ~$160 per transaction. High-conviction Masters bets and larger-ticket crypto and political positions both contributed to the ticket-size expansion.
Politics (including Elections) dipped 19.6% WoW to $46.9M, despite the California Governor race and other election markets beginning to build steam. The CA governor winner market alone is now over $21.6M in notional volume on Kalshi, and is drawing more interest with Swalwell now out of the race.
Kalshi Category Breakdown Week of April 6-11
*Other includes: Unknown ($83.0M), Mentions ($21.1M), Science & Technology ($1.6M), Social ($791K), Companies ($726K), World ($387K)
Polymarket Trump category doubles as fees hit $7.73M
Polymarket’s week was headlined by a structural shift in what’s driving volume. The platform posted $2.48B in notional (+25.5% WoW), but the transaction count was essentially flat (-1.5%). That means average trade size grew 27.5% to $110.77, which could be a signal that larger, more sophisticated capital is flowing into Polymarket’s political and macro markets.
On the fee front, Polymarket generated $7.73M for the week, up from $2.23M the week of March 23, before its March 30 fee overhaul. Polymarket held 92.9% of all on-chain prediction market fee revenue last week, with the total tracked on-chain market producing $8.32M for the week.
The Trump category led the WoW volume charge, more than doubling (+141% WoW) to $488.3M, now Polymarket’s second-largest single category at 19.7% of total volume, behind only Sports. Combined with the broader Politics category ($354.2M, +7.9% WoW), the Trump + Politics complex hit $842.5M, or 34.0% of all Polymarket volume for the week. Markets driving recent activity include US–Iran conflict markets, 2028 US presidential election markets, the April Fed rate decision, World Cup winner, and F1 Drivers’ Championship. Polymarket’s main Masters winner contract had $126M in volume. The breadth of the key drivers spanning geopolitics, long-horizon elections, macro policy, and global sports signals that Polymarket is increasingly being used as a macro positioning tool across categories.
Sports crossed $1.04B for the week (+25.3% WoW), its strongest performance outside of NCAA tournament weeks, powered by $108M+ across all Masters markets on the platform. Crypto was the only category in the red, dipping 5.9% to $474.6M. Polymarket’s elevated crypto fee rate (up to 1.80% peak effective rate vs. 0.75% for sports) may be moderating high-frequency speculative activity in that category.
Polymarket Category Breakdown Week of April 6-11
*Other includes: Tech ($8.1M), Other ($3.1M), World ($81K)
Kalshi’s average trade size 45% larger than Polymarket
A few dynamics stand out across the six-week window on Kalshi vs. Polymarket. Note, per usual, Polymarket global serves a vastly different audience as it’s not legally accessible to US customers. Kalshi’s notional volume lead reached a six-week high of $1.06B this week, up from $932M the prior week and from a low of $362M at the start of March. Kalshi’s sports-heavy mix consistently performed well during March Madness and is finding sustained volume drivers, with the Masters steering the ship this week.
The transaction divergence is one of the more interesting trends. Polymarket’s transaction count has been declining since its March 16 peak of 27.4M, while Kalshi’s rose this week to 22.2M. The two platforms are now nearly matched on raw transaction count (22.4M vs. 22.2M) despite Kalshi’s $1B+ volume lead, meaning Kalshi’s average trade size (~$160) is nearly 45% larger than Polymarket’s (~$111). The divergence reflects platform mix: Kalshi’s Sports users make larger individual bets, while Polymarket’s political and crypto market traders, though placing larger bets than they used to, are still conducting more frequent smaller trades.
| Metric | Kalshi Apr 6–11 | Kalshi WoW | Polymarket Apr 6–11 | Polymarket WoW |
|---|---|---|---|---|
| Notional Volume | $3,539,299,989 | +21.8% | $2,475,772,644 | +25.5% |
| Transactions | 22,157,345 | +10.2% | 22,349,643 | –1.5% |
| Avg. $ per Transaction | ~$159.70 | +10.5% | ~$110.77 | +27.5% |
| Weekly Fees | — | — | $7.73M | +23.5% |
Looking ahead
Primary election markets are heating up, and the California Governor primary June 3 will continue to drive outsized volume over the next several weeks. With Swalwell out, the field reshuffles around Steyer, Porter, Mahan, and others. Each major development including endorsements, polling, and debate performances will generate volume spikes on both platforms. The $22M+ already traded on the two main related Kalshi markets is likely to double before the primary closes.
Expect sports markets to continue to dominate in the coming weeks, especially on Kalshi, with NHL and NBA playoffs gearing up to start, World Cup betting ramping up, MLB underway, and several other non-major sports attracting sustained volume.
April fed rate decision markets are also active on both platforms, currently trending at 98% for no rate change. A hold, cut or surprise move would generate significant volume surges on adjacent markets across economy and Trump-related policy markets. One of the major drivers of Polymarket’s Trump category surge this week are US-Iran conflict markets. Geopolitical event markets have proven to pull large-dollar bets and attract media coverage, which feeds further volume. This category remains active heading into a new week, and could help push Polymarket into new all-time high territory along with Kalshi.
