Prediction markets processed $6.41 billion in notional volume during the week of March 16–22, 2026 — a new all-time high. Kalshi posted $3.40 billion, Polymarket added $2.54 billion. The NCAA Tournament alone generated over $2 billion in trades on Kalshi in four days, producing $25 million in pla...
"When anyone can use prediction markets to make a well-timed bet on Congress passing a bill, government decisions, or a military strike, it's ripe for corruption and erodes public trust." — Jeff Merkley, U.S. Senator (D-Oregon)
Prediction markets processed $6.41 billion in notional volume during the week of March 16–22, 2026 — a new all-time high. Kalshi posted $3.40 billion, Polymarket added $2.54 billion. The NCAA Tournament alone generated over $2 billion in trades on Kalshi in four days, producing $25 million in platform fees. At February 2026's combined run rate of $16.8 billion per month, the industry is on pace to exceed $200 billion in annualized volume.
Simultaneously, two bipartisan Senate bills introduced within 72 hours of each other seek to ban prediction market contracts on sports, politics, elections, and military actions. Kalshi closed a $1 billion funding round at a $22 billion valuation on March 19. Polymarket is seeking $20 billion. The sector is raising capital at a pace that outstrips the legislative machinery attempting to constrain it. Whether regulation catches the market or the market outgrows the regulators is the central question for the next 90 days.
The prediction market sector established a new weekly volume record of $6.41 billion for the period March 16–22, 2026, according to DeFi Rate aggregated data. The breakdown:
| Platform | Weekly Volume (Mar 16–22) | Week-over-Week Change | Market Share | |---|---|---|---| | Kalshi | $3.40B | Record | 53.0% | | Polymarket | $2.54B | +8.5% | 39.6% | | Other platforms | ~$0.47B | — | 7.4% |
The prior week (March 9–15) had already set a record at $5.89 billion across all tracked platforms. Two consecutive record weeks indicate structural demand growth rather than a one-off event spike.
Sports contracts drove the surge. Combined sports volume across Kalshi and Polymarket reached $3.01 billion for the week — $1.99 billion on Kalshi, $1.02 billion on Polymarket — making sports the single largest category. Polymarket's sports volume increased 32% week-over-week as Round 1 of the NCAA Tournament commenced.
On a single-day basis, Polymarket recorded $478 million in notional trading volume on March 1, 2026. The politics category alone accounted for $220 million of that total.
The NCAA men's basketball tournament has become the defining test case for prediction markets as a consumer product. March 19 — the first day of tournament games — was the second-largest trading day in Kalshi's history, trailing only the 2026 Super Bowl. Over the first four days of the tournament, Kalshi processed more than $2 billion in trades and collected $25 million in fees. Over the following weekend, users traded an additional $800 million in tournament-linked contracts.
According to Sports Illustrated, the $800 million traded over the tournament's first weekend was nearly double the total volume across the full three-week span of the 2025 tournaments. Year-over-year growth of this magnitude in a single event category suggests the platform is acquiring users at a rate that compounds on itself.
Kalshi has deployed a marketing instrument around the tournament: a bracket contest offering $1 billion to any participant who correctly predicts all 63 tournament games. While the probability of a perfect bracket is approximately 1 in 9.2 quintillion (making a payout effectively impossible), the contest functions as a user acquisition mechanism. The $33.1 million in fees Kalshi earned during the record week represents the actual revenue generated by the event.
The NCAA has publicly objected to prediction market contracts on its tournament games. According to Bloomberg, Kalshi continued to list tournament contracts despite these objections, operating under CFTC authority rather than state sports betting frameworks.
Private capital has entered the sector at an accelerating rate. Three data points define the current cycle:
Kalshi: $22 billion valuation. On March 19, 2026, Kalshi closed a $1 billion funding round led by Coatue Management, according to Bloomberg. The round valued the company at $22 billion — double its $11 billion valuation from December 2025, and 11x its $2 billion valuation from June 2025. Kalshi's annualized revenue run rate is approximately $1.5 billion.
Polymarket: $20 billion target. Polymarket, last valued at $9 billion following a $2 billion strategic investment from Intercontinental Exchange (NYSE owner) in October 2025, is exploring a new round at approximately $20 billion, according to the Wall Street Journal. Secondary market data from PM Insights places the current implied valuation at $11.6 billion. The company has raised $2.3 billion in total funding across seven rounds from 36 investors.
5c(c) Capital: Dedicated VC fund. On March 23, 2026, former Kalshi employees Adhi Rajaprabhakaran and Noah Zingler-Sternig announced 5c(c) Capital, a venture fund raising up to $35 million to back approximately 20 prediction-market-adjacent startups over two years. The fund is named after a clause in the Commodity Exchange Act. Backers include both Kalshi CEO Tarek Mansour and Polymarket CEO Shayne Coplan — competitors jointly funding the ecosystem. Additional backers include Marc Andreessen (via Moneta Luna) and Ribbit Capital founder Micky Malka. The fund's first close is expected within 30 days.
Combined, the two leading platforms have a blended valuation exceeding $30 billion. The sector has absorbed more than $3 billion in private capital since October 2025.
Three distinct regulatory vectors converged in March 2026:
Bill 1: Prediction Markets Are Gambling Act (March 23). Senators Adam Schiff (D-CA) and John Curtis (R-UT) introduced the first bipartisan Senate bill targeting prediction markets. The bill would prohibit any CFTC-registered entity from listing contracts that "closely resemble a sports bet or casino-style game." It targets the Super Bowl and March Madness contracts that have become Kalshi's highest-revenue products. The bill reinforces what sponsors characterize as Congress's original intent under the Commodity Exchange Act — that the Act does not permit sports gambling.
Bill 2: STOP Corrupt Bets Act (March 26). Senator Jeff Merkley (D-OR) and Representative Jamie Raskin (D-MD) introduced a broader bill banning event contracts on elections, sports, government actions, and military operations. The bill is cosponsored by Senators Warren, Blumenthal, Van Hollen, and Whitehouse. It would mandate a Government Accountability Office study of prediction markets, insider trading risks, and effects on minors. This bill goes further than the Schiff-Curtis proposal by explicitly targeting political and military event contracts — Polymarket's core categories.
CFTC Rulemaking. The CFTC published an Advance Notice of Proposed Rulemaking (ANPRM) requesting comment on regulation of event contracts traded on prediction markets, with comments due April 30, 2026. In February 2026, the CFTC formally withdrew a prior proposed rule that would have broadly classified political and sports event contracts as "contrary to the public interest." The withdrawal signaled regulatory openness; the two Senate bills signal legislative pushback against that openness.
The jurisdictional picture remains fragmented. A New Jersey federal court granted Kalshi a preliminary injunction based on federal CFTC preemption. A Nevada federal court subsequently ruled that state gaming regulations can apply. Arizona has filed criminal charges against prediction market activity alleging illegal gambling and election wagering. The CFTC filed an amicus brief in the Ninth Circuit affirming exclusive federal jurisdiction over event contract markets.
Kalshi's response: banning sports contracts on prediction markets would "just push this behavior offshore, where no regulation exists."
The regulatory debate is complicated by the sector's integration into mainstream financial platforms:
Robinhood-Kalshi partnership. Robinhood, which has 23+ million funded accounts, distributes Kalshi contracts through its platform. According to industry reports, Kalshi generates approximately 60% of its total trading volume through this partnership. Robinhood announced in late 2025 a joint futures and derivatives exchange with Susquehanna International to further expand prediction market services.
DraftKings Predictions. DraftKings launched prediction market products on December 19, 2025, in 38 states — including California and Texas, where traditional online sports betting is unavailable. This is notable because it provides prediction market access in 12 states beyond the reach of legal sportsbooks. DraftKings operates as a state-regulated entity rather than under CFTC authority.
FanDuel Predicts. FanDuel launched December 22, 2025, initially in five states (Alabama, Alaska, South Carolina, North Dakota, South Dakota) with a phased national rollout through early 2026.
The distribution footprint complicates legislative action. Banning CFTC-registered prediction market contracts does not address state-regulated prediction products offered by DraftKings and FanDuel. Any comprehensive ban would require coordination between federal commodities regulation and state gaming commissions — a jurisdictional alignment that does not currently exist.
The economic structure of prediction markets reveals why the sector attracts capital and regulatory scrutiny simultaneously.
Revenue model. Kalshi's $33.1 million in fees during its record week translates to an approximate take rate of 0.97% on $3.4 billion in notional volume. At the current annualized revenue run rate of $1.5 billion, Kalshi's price-to-revenue ratio is approximately 14.7x at its $22 billion valuation. For comparison, Coinbase trades at approximately 12x revenue and Robinhood at approximately 10x.
Value distribution. Unlike decentralized protocols where transaction fees fragment across validators, stakers, and MEV extractors, prediction markets concentrate value at the platform layer. The operator captures the full fee. Liquidity providers (market makers) capture the bid-ask spread. Users bear the full cost of both. There is no validator subsidy, no token emission, no inflationary mechanism funding operations.
Market structure. Kalshi and Polymarket function as a near-duopoly, commanding approximately 93% of tracked volume. This concentration creates pricing power but also regulatory surface area — two entities can be regulated more effectively than a decentralized ecosystem of thousands.
Crypto-native vs. regulated. Polymarket operates on Polygon with USDC settlement, making it accessible globally but legally ambiguous in the U.S. (it geo-blocks U.S. users for most products). Kalshi operates as a CFTC-registered Designated Contract Market — fully regulated, U.S.-only, with fiat settlement. The two models represent different points on the decentralization-compliance spectrum.
The prediction market sector is experiencing simultaneous capital inflow and regulatory acceleration. The data suggests the industry has reached a scale — $200 billion annualized volume, $30+ billion combined valuation — that makes it impossible for legislators to treat as a niche. The two Senate bills introduced this week are the first substantive legislative attempts to constrain the market, but their scope is limited by jurisdictional fragmentation between CFTC authority and state gaming commissions.
The 90-day window between now and the CFTC's April 30 comment deadline will determine whether prediction markets are classified as regulated financial products, gambling instruments, or something in between. The answer determines which regulatory framework — federal commodities law, state gaming codes, or new purpose-built legislation — governs a market that processed $6.4 billion in a single week.
The economic value is real: $1.5 billion in annualized revenue for Kalshi alone, with no token subsidies or inflationary mechanics propping up the model. Whether the regulatory structure catches up to the economic reality remains an open question.