Prediction markets processed $44.8 billion in combined monthly trading volume in June 2026, more than triple the approximately $14 billion average monthly handle of all legal U.S. sportsbooks in 2025. That figure now sits at the center of a jurisdictional clash between 44 state attorneys general ...
"If your revenue equals your customers' losses, you have a different business model." — Tarek Mansour, CEO, Kalshi
Prediction markets processed $44.8 billion in combined monthly trading volume in June 2026, more than triple the approximately $14 billion average monthly handle of all legal U.S. sportsbooks in 2025. That figure now sits at the center of a jurisdictional clash between 44 state attorneys general and the Commodity Futures Trading Commission over who regulates event contracts — a fight that will determine whether a $45 billion monthly market operates as a federally supervised derivatives exchange or as an unlicensed gambling operation.
On July 27, U.S. District Judge Katherine Menendez granted a preliminary injunction blocking Minnesota's felony prediction-market ban four days before it took effect. On July 28, a coalition of 44 state attorneys general submitted a letter to the CFTC arguing the agency lacks authority over sports event contracts. The two events, arriving within 24 hours of each other, frame the central regulatory question of 2026: does the Commodity Exchange Act preempt state gambling law when applied to federally registered event contracts?
The economic stakes are direct. States estimate they are losing over $600 million annually in sports betting tax revenue to prediction market platforms that pay no state gaming taxes. Three states — Kentucky, Illinois, and North Carolina — have already enacted prediction market taxes. At least 15 states have introduced legislation in 2026 addressing the sector. Meanwhile, Kalshi's valuation has reached $22 billion, Polymarket hit an estimated $1 billion in annualized revenue in June 2026, and monthly active wallets on Polymarket's Polygon-based infrastructure nearly tripled to 840,000 in the six months through February 2026.
Combined monthly trading volume on Kalshi and Polymarket reached $44.8 billion in June 2026, a 75% surge from May's $25.66 billion, according to data compiled by The Block. Kalshi accounted for $31.5 billion of the total, an 87.4% month-over-month increase. Polymarket's non-U.S. platform contributed $10.26 billion, up 45% from $7.08 billion in May.
The growth trajectory is steep. According to Pew Research Center, combined monthly global trading volume on the two platforms rose from under $5 billion in September 2025 to approximately $24 billion by April 2026. TRM Labs data shows the broader arc: monthly volume scaled from $1.2 billion in early 2025 to over $20 billion by January 2026, with a single-day record of $425 million set on February 28, 2026.
User growth parallels volume. Monthly unique wallets on Polymarket nearly tripled to 840,000 in the six months through February 2026, according to TRM Labs. Monthly active traders across the platform grew from approximately 4,000 in January 2024 to over 734,000 by March 2026, an increase of 18,250% in 26 months.
The composition of trading has shifted. According to TRM Labs, "geopolitics, macroeconomics, and politics — not crypto — now drive" primary trading activity. In February 2026, the top market was "Will the US strike Iran?" at $252.7 million across 23 sub-markets. Sports contracts, while a major category on Kalshi, coexist with contracts on Fed decisions ($115.6 million in February), inflation, weather, and geopolitical events.
On July 27, 2026, U.S. District Judge Katherine Menendez of the District of Minnesota granted a preliminary injunction blocking enforcement of SF 3432, a state law that would have made it a felony to create, operate, or help administer prediction markets. The law was set to take effect on August 1.
The ruling centered on federal preemption under the Commodity Exchange Act (CEA). Judge Menendez found that the plaintiffs — the Department of Justice, the CFTC, Kalshi, and Polymarket US — "have met their burden to show they are likely to succeed, at least in part." The court concluded that Congress gave the CFTC exclusive jurisdiction over transactions in swaps and that Kalshi and Polymarket US operate as designated contract markets under that federal framework.
The judge's analysis acknowledged limits. "The Minnesota statute may not be preempted in all its applications," Judge Menendez wrote. "But the Court finds the state law is likely preempted in many respects." The injunction protects only CFTC-registered designated contract markets, not all prediction market providers.
The Minnesota case follows a pattern. On April 6, 2026, the Third Circuit Court of Appeals affirmed a preliminary injunction for Kalshi against New Jersey on similar federal preemption grounds. A federal judge permanently blocked Arizona from pursuing criminal charges against Kalshi. Nevada secured a temporary ban through the Ninth Circuit in March 2026 that remains in effect. Michigan, Illinois, Connecticut, and Massachusetts have active litigation.
Minnesota Attorney General Keith Ellison disagreed with the decision, characterizing prediction markets as gambling and stating that Minnesota retains the right to protect residents from unlicensed activity.
On July 28, 2026 — one day after the Minnesota ruling — a coalition of 44 state attorneys general submitted a letter to the CFTC as the public comment period on its proposed rulemaking closed. The letter, led by Ohio Attorney General Andy Wilson, argued that the CFTC lacks statutory authority to regulate sports-related event contracts, according to CNBC.
The coalition's position rests on three arguments: states have regulated sports betting for more than a century; the CFTC has no expertise in gaming regulation; and sports event contracts on prediction market platforms sidestep state licensing requirements, tax obligations, and integrity rules.
The states contend that the vast majority of business on prediction market platforms constitutes sports betting. On Kalshi, sports trading is the dominant category. The states argue these contracts function as unregulated sportsbooks operating in all 50 states, including states that prohibit or restrict sports wagering.
The 44-state coalition represents an escalation. In June 2026, coalitions of 37-plus attorneys general filed amicus briefs in Ohio and other states pushing back on CFTC preemption claims. The growth to 44 states by late July signals increasing coordination.
The CFTC's position is the opposite. In a separate action, the agency filed an amicus brief in the Sixth Circuit reaffirming its claim to exclusive jurisdiction over prediction markets, according to a July 2026 CFTC press release.
The financial motivation behind state opposition is quantifiable. According to MultiState, state regulators estimate they are losing over $600 million annually in sports betting tax revenue to prediction market platforms that pay no state gaming taxes.
The tax disparity is structural. Prediction markets operate as federally regulated derivatives exchanges, subject to CFTC oversight but not state gaming taxes. Sportsbooks pay state taxes ranging from 6.75% in Nevada to 51% in New York. According to a Tax Policy Center analysis, the tax wedge in Rhode Island reaches as high as 44%, meaning a $100 loss on a sports betting application generates $44 more in state tax revenue than the same wager placed on a prediction market platform.
Three states have moved to close the gap legislatively. Kentucky enacted a 14.25% excise tax on prediction market operators' transaction fees in April 2026. North Carolina imposed a 6% tax on net trading fee revenue apportionable to the state. Illinois is considering steeper sports betting taxes alongside new prediction market rules.
Super Bowl trading volume on prediction markets surpassed $1 billion in 2026. A single March Madness winner contract exceeded $100 million in volume. These figures represent direct competition with state-licensed sportsbooks for the same bettor dollar.
On June 10, 2026, the CFTC issued a Notice of Proposed Rulemaking (NPRM) proposing amendments to Rule 40.11 and a new Appendix F to Part 40. The proposed framework establishes a three-step analytical process for evaluating event contracts.
Step one determines whether a contract "involves" one of the enumerated categories: unlawful activity, terrorism, assassination, war, or gaming. Step two assesses whether the contract is "contrary to the public interest." Step three applies a contract-by-contract review.
The practical effect, according to analysis by Proskauer Rose and Mayer Brown, is that the CFTC would retain authority over most event contracts while banning contracts on extreme events (assassination, terrorism, war). Sports contracts would face heightened scrutiny but would not be categorically banned, a position that has drawn opposition from both the 44-state coalition and the gambling industry.
The public comment period closed on July 27, 2026 — the same day Judge Menendez issued the Minnesota injunction. The CFTC's March 2026 Advance Notice of Proposed Rulemaking had previously asked broader questions about swap classification and the application of CFTC regulations to blockchain-based prediction markets.
Polymarket operates on the Polygon blockchain, with all trading, clearing, and settlement denominated in USDC. This is not an abstraction. Every position, every trade, every payout settles on-chain with near-instant finality. The platform's Conditional Token Framework (CTF) exchange contract on Polygon has processed billions in USDC volume.
This architecture creates a direct link between prediction market growth and on-chain stablecoin demand. Polymarket's $14 billion surge in early 2026 boosted USDC demand on Polygon, according to Blockchain News. The platform's growth contributed to Polygon processing $79 billion in stablecoin volume, according to CoinLaw statistics.
The regulatory question has implications for on-chain infrastructure. If states successfully argue that sports event contracts are gambling rather than derivatives, Polymarket's Polygon-based settlement layer would face the same regulatory classification. The distinction between a blockchain-settled derivative and a blockchain-settled wager has not been adjudicated.
Kalshi operates on centralized infrastructure as a CFTC-designated contract market. Its $22 billion valuation, reported as of mid-2026, reflects the regulatory arbitrage between federal derivatives classification and state gambling law.
Growth has brought scrutiny. TRM Labs identified suspicious trading activity around geopolitical events. In one documented case, four coordinated wallets converted approximately $40,000 into $872,000 betting on Iran airstrikes, exhibiting synchronized funding and exit patterns.
TRM Labs data on user segmentation reveals a concentrated market structure. Mid-frequency traders (11-1,000 trades) account for 44.7% of activity, while high-frequency market makers (over 10,000 trades) represent 35.2%. Single-trade participants contribute less than 0.2% of activity. The market is not dominated by retail.
Kalshi CEO Tarek Mansour acknowledged in an Axios interview in April 2026 that fast-growing prediction markets will attract fraud and insider trading, stating that investigators will "inevitably" expose and punish bad actors.
Congress has introduced competing legislation. The Prediction Markets Are Gambling Act, introduced by Senators John Curtis (R-UT) and Adam Schiff (D-CA), would prohibit CFTC-registered entities from listing any prediction contract that resembles a sports bet or casino-style game. Companion legislation was introduced in March 2026 by Schiff, Curtis, and Catherine Cortez Masto.
The bill represents the legislative counterpart to the states' regulatory argument: if the CFTC will not relinquish jurisdiction, Congress can remove it.
Meanwhile, the Trump administration's proposed rulemaking takes a middle path — banning contracts on war, assassination, and other extreme events while allowing many sports contracts to continue operating. The administration's approach is closer to the CFTC's institutional position than to the states' categorical opposition.
The prediction market regulatory battle is a jurisdictional conflict with $45 billion in monthly volume at stake. The federal preemption argument has prevailed in two circuit-level decisions, but 44 states are not conceding. The CFTC's proposed rulemaking, the 44-state letter, and the Minnesota injunction all arrived within a single week, suggesting the conflict is accelerating rather than resolving.
The economic structure of the dispute is straightforward: prediction markets operating as federally regulated derivatives pay no state gaming taxes. States that legalized sports betting expected to tax a defined market. Prediction markets expanded that market outside state control. The $600 million annual tax revenue gap is the quantifiable cost of the jurisdictional ambiguity.
For Web3 infrastructure, the outcome matters directly. Polymarket's Polygon-based settlement layer processes billions in USDC. If prediction markets are reclassified as gambling in certain states, the on-chain infrastructure that clears and settles those contracts faces the same reclassification. The distinction between a blockchain-settled derivative and a blockchain-settled wager remains unresolved.
The CFTC's final rule, expected later in 2026, will set the parameters. The courts will determine whether those parameters hold. The states have made clear they intend to fight on every front — regulatory, legislative, and judicial — simultaneously.