Kalshi Surpasses Polymarket as #1 Global Prediction Market by Volume

When the CFTC formally classified prediction markets as derivatives in March 2026, it did not just hand Kalshi a regulatory win. It ratified a strategy two years in the making. By the time Bloomberg and Dune Analytics confirmed Kalshi as the world’s largest prediction market by trading volume in late April 2026, regulation was no longer a hurdle for the company — it was its widest moat.

The dominance flip

For most of 2024, the prediction-market story was Polymarket’s. The crypto-native exchange ran on USDC, courted international users, captured the Trump-vs-Harris election cycle, and at year-end commanded roughly 95% of all prediction-market trading volume. Kalshi, the CFTC-regulated US exchange, was the small, slow, regulated cousin trading well under 5% of sector activity.

Sixteen months later, the picture has inverted. By September 2025, Kalshi held about 62% of weekly notional volume against Polymarket’s 38%. By April 2026, that lead had widened to roughly 65/35 — and the absolute numbers were running at a different scale entirely.

Year-to-date through April 20, 2026, Kalshi had cleared $37.49 billion in notional trading volume against Polymarket’s $29.23 billion — a roughly $8 billion lead, opening at a pace of more than $1 billion per week. The shift is not subtle. It is structural. And it traces back to the part of the business Polymarket spent years working around: federal regulation. Industry watchers had already flagged this as the central thread of the broader prediction market wars.

How regulation became Kalshi’s moat

Kalshi’s strategic bet, taken before Polymarket’s 2024 election surge, was that the path to scale in event contracts ran through the Commodity Futures Trading Commission rather than around it. That bet looked questionable for years. The CFTC initially blocked Kalshi’s election markets and pursued the company in court. By 2025, the calculus had inverted.

In May 2025, Kalshi prevailed in its lawsuit against the CFTC over election markets. The agency, under a new administration, dropped its appeal. By December 2025, the CFTC had a new chairman — Michael Selig — whose early posture was deferential to the prediction-market industry absent a clear judicial directive otherwise. Then, in March 2026, the CFTC formally determined that prediction markets are derivatives, providing a federally compliant pathway for the entire category.

“Event contracts have generated high demand because they provide a maximally direct way to get exposure to events.”
— Jack Such, Kalshi business and media development

The March 2026 ruling did two things at once. It cemented Kalshi’s existing operating model as the legally clean way to run an event-contract market in the United States, and it removed the meaningful regulatory headwind on US institutional partnerships — clearing brokers, market makers, and retail platforms that had previously been wary of touching prediction markets at scale. Polymarket, which still operates through blockchain settlement for its non-US users, could not match either side of that equation overnight. State-level fights — including Kalshi’s ongoing legal war headed toward the Supreme Court — continue, but the federal lane is now clear.

Volume tells the story

The lead is not noise. Across the six weeks ending April 13, 2026, Kalshi posted higher notional volume than Polymarket every single week — and the gap kept expanding into Masters week before both platforms pulled back as the major sporting calendar quieted.

Masters week told the most useful version of the story. Kalshi traded $3.54 billion notional in the week of April 6 — its highest single-week total ever, including roughly $545 million tied to the golf major itself. Polymarket cleared $2.48 billion. When the tournament ended and short-dated Trump-related markets expired on Polymarket, the platform’s volume collapsed faster than Kalshi’s. Sports liquidity, it turned out, was Kalshi’s ballast.

Distribution: the Robinhood and xAI multipliers

Regulatory clarity is leverage only if you can put the product in front of users. Kalshi’s second strategic edge is distribution — and specifically, retail-grade distribution that Polymarket’s permissionless on-chain model has had a harder time replicating in the United States.

In August 2025, Robinhood launched pro and college football contracts via a Kalshi integration. By Q2 2025, Robinhood users were trading roughly $1 billion in Kalshi contracts in a single quarter. By the time the duopoly shipped at scale into 2026, Robinhood was driving more than half of Kalshi’s total notional volume — making the brokerage, in effect, the largest single distribution channel in the prediction-market industry. Robinhood has since announced its own derivatives exchange via the LedgerX/MIAXdx purchase, but it has explicitly said it will keep offering Kalshi contracts alongside its own product when MIAXdx goes live.

The other partnership is less load-bearing on volume but matters for the user experience. In July 2025, Elon Musk’s xAI integrated Grok with Kalshi, allowing traders to query the model for breaking news, historical odds, and economic indicators inside the trading flow. xAI has the same arrangement with Polymarket — but for Kalshi traders, who tend to skew toward US fiat-funded retail and institutional accounts, the AI overlay is a clean fit on top of an already mainstream onboarding experience.

Sports as the volume engine

The third leg of Kalshi’s surge is sports. In February 2026, Kalshi reported more than $1 billion in trading volume on Super Bowl Sunday alone — up roughly 2,700% year-over-year. Super Bowl week hit $2.8 billion. CEO Tarek Mansour disclosed the figures publicly; a separate Fortune estimate placed Sunday turnover at $871 million, but even that more conservative number represented an order-of-magnitude leap from the $27 million in volume tied to the prior year’s Super Bowl.

“The long-term vision is to financialize everything and create a tradeable asset out of any difference in opinion.”
— Tarek Mansour, Kalshi co-founder and CEO

The sports vertical is now the dominant share of Kalshi’s mix. In the week of April 13, sports contracts accounted for $2.26 billion of Kalshi’s $3.06 billion in volume — roughly 73.7%. Kalshi has also outperformed traditional sportsbooks on March Madness pricing, suggesting the platform is competing not just with Polymarket but with the established US sportsbook industry. Bets on the Super Bowl 2026 halftime show — Bad Bunny’s first song — alone exceeded $100 million.

The full picture: a timeline of compounding wins

None of these moves alone explains the crossover. Stacked together over twelve months, they form the strategic arc that took Kalshi from regulated also-ran to global category leader.

Polymarket was not idle through this period. The company secured a $1 billion ICE investment at a $9 billion valuation in October 2025, added a further $600 million from ICE in March 2026, started charging trading fees to build a real revenue line, and re-entered the US market through a regulated relaunch. But the curve of those moves did not match the curve on Kalshi’s side — and notably, Polymarket’s most recent fundraising target, $15 billion, sits a full $7 billion below Kalshi’s most recent mark.

Why the US is now Kalshi’s moat

Globally, Kalshi has a roughly two-thirds majority of weekly trading. Inside the United States — the only market where most retail brokerage rails are even available — the gap is not a contest.

Polymarket’s US relaunch happened only after years on the sidelines, and it relaunched into a market where Kalshi already had Robinhood’s distribution rails, regulated clearing, and a sports vertical that made it the default brand for retail US event traders. The 89% US share is not just a snapshot — it is the lever that gives Kalshi outsized weight in the global numbers, because the US accounts for the bulk of fiat-denominated volume.

What Polymarket still owns

Polymarket has not been displaced — it has been outflanked on the regulated US side while keeping real strengths elsewhere. The platform still leads on international, crypto-native trading, runs a more diverse market mix (sports 46%, crypto 22%, politics 21% in mid-April 2026 versus Kalshi’s sports-heavy 74%), and is positioned to capture a different kind of user: the on-chain trader who values self-custody, USDC settlement, and access in jurisdictions where Kalshi cannot operate.

The valuation gap is the cleanest summary of how investors are pricing those two profiles. Kalshi’s last round, led by Coatue and others, came in at $22 billion against a stronger US revenue line and tighter alignment with the regulated derivatives stack. Polymarket’s $15 billion target reflects a real business with international reach — but one that, in the eyes of the market, carries crypto-token expectation risk and a less defensible US position. Wash-trading concerns from late 2024 — by some estimates, 60% of Polymarket’s December 2024 volume — have largely subsided, but the structural read remains: investors want fee revenue, US distribution, and regulatory certainty, and Kalshi has more of all three. Coatue’s role in Kalshi’s $1 billion raise at a $22 billion valuation made that read explicit.

“Polymarket’s volume is being read as pure product demand. Airdrop farming is why that read is misleading.”
— Eric Chen, Injective cofounder

A bigger pie

Kalshi’s lead is less interesting, in a sense, than the size of the market it is leading. Total prediction-market volume hit $63.5 billion in 2025, a roughly 4x year-over-year jump. By January 2026, monthly industry volume had crossed $20 billion. Citizens Bank projects the category could generate $10 billion in annual revenue by 2030; Bernstein projects $1 trillion in annual trading volume by the same date.

Whether either of those numbers proves correct, the trend line says this is no longer a niche financial product. Kalshi has won the first decisive round, and it has done so by treating regulation as infrastructure rather than friction. Traders trying to size positions or compare cross-platform pricing can use our expected value calculator to translate prediction-market quotes into break-even probabilities.

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Sources

• Commodity Futures Trading Commission — federal regulator that issued the March 2026 derivatives determination and the underlying 2025 court ruling on Kalshi’s election markets
• Kalshi News and Company Communications — official Kalshi disclosures including Super Bowl 2026 trading volume and the $22 billion valuation announcement
• CNBC: Kalshi says Super Bowl trading volume surpassed $1 billion — Tarek Mansour interview, year-over-year comparisons
• Fortune: Investors are valuing Polymarket at a discount to archrival Kalshi — $7B valuation gap analysis, US market share, airdrop-farming concerns
• CoinDesk: Robinhood partners with Kalshi to launch football prediction markets — terms of the August 2025 distribution partnership
• CoinDesk: Elon Musk’s xAI partners with Kalshi — Grok integration announcement
• CNBC / Bernstein: Prediction markets will grow to $1 trillion by 2030 — sell-side projection cited in industry-context section