Beyond the Final Score and the Rise of Sports Event Trading

On Sept. 23, Pew Research Center published a count that puts a size on something sports fans have been watching grow all year. Combined monthly trading on Kalshi and Polymarket, the two leading prediction markets, went from $26 billion in May to $53 billion in July. Pew put most of that jump down to sports, which it now finds is the most traded topic on both platforms by a wide margin.

The World Cup explains part of it. Across the two World Cup months, Pew counted sports trading above $58 billion on Kalshi and close to $22 billion on Polymarket. August slipped to a combined $47 billion, and early figures for this month were rising again as football returned. Pew has also found that sports traders tend to place more trades than people who stick to other topics, a finding from its earlier study of the typical Polymarket user.

What's changed is less the volume than the menu. A fan who once had one question to trade, who wins, now finds contracts on the margin, the combined score, a player's night, a season's awards and whether a named athlete takes the field at all. Each step away from the scoreboard raises a different question: who sets the price, who may offer the contract, and who might already know the result.

Margins And Totals Settle On The Same Box Score As The Winner

The first step past the final score barely leaves it. A margin contract asks whether a team wins by more than a set number of points. A totals contract asks whether both teams together clear a line. Both settle on the official result, the same number that decides the winner, so nobody has to trust a new source of truth.

Polymarket's early filings with the Commodity Futures Trading Commission show how natural that step is. According to Prediction News, the contracts it self-certified before relaunching in the US already included point spreads and totals alongside plain winners.

The federal regulator has been comfortable here too. The CFTC's June proposal offered a detailed defense of contracts on a game's outcome or a team's general performance, describing teams as economic enterprises. "Just as the corn futures market is about more than just corn, a prediction market about one sporting event is about more than just that sporting event," the document states, as ESPN reported.

Critics don't buy the comparison, and the American Gaming Association called the framework an attempt to redefine sports betting. State gaming boards contest even game-winner contracts in court, as the last section shows. Inside the CFTC's own proposal, though, the scoreboard end of the menu draws no objection, and the agency's concerns start further out.

A Price Moves In Cents, And The Taker Pays For The Move

Every one of these contracts trades between zero and one dollar. A "Yes" bought at 40 cents returns a dollar when the outcome occurs and zero otherwise, so the price doubles as the market's rough estimate of the chance. No house sets it from a trading desk. Buyers and sellers post orders, and the price sits wherever the two sides meet.

That makes a headline number easy to misread. Pew measures volume at each contract's $1 face value rather than the price paid, so a contract bought at 20 cents enters the count as a full dollar. The $53 billion is a measure of contracts changing hands. It isn't a tally of money put at risk, which would be smaller.

Prices move when information arrives. An injury designation, a surprise inactive or a weather report can shift a contract several cents before kickoff, and whoever acts first takes the price that's sitting on the book. The help center for Polymarket's international exchange says only those takers pay a fee. Traders who post orders and wait pay no fee, and sports carries a listed taker rate of 0.05. The fee in dollars is symmetric around 50 cents, so a trade at 30 cents costs the same as one at 70.

None of those rules are universal. Tick sizes, minimum orders, fees and settlement procedures are written by each venue, which is why the venue itself belongs in any honest account of how these prices work.

Polymarket Came Back To The US With Sports First

Polymarket's road to selling Americans a sports contract was a long one, because it first had to shut out American users. On Jan. 3, 2022, the CFTC ordered Blockratize, the company behind Polymarket, to pay a $1.4 million penalty and wind down markets that didn't comply with federal commodities law. The order said it had run more than 900 event markets since 2020 without registering as an exchange.

The route back ran through a purchase. In the summer of 2025 Polymarket bought QCX, a CFTC-licensed exchange and clearinghouse, for $112 million, and The Block reported that it received clearance late that year under an amended order of designation. The US app began reaching people on its waitlist on Dec. 3, 2025. "We're launching with sports," the company posted, and Prediction News found only NFL and NBA game winners live at first.

That sequence decides which parts of the menu a US fan actually meets. The regulated US entity, not the international site, chooses which contract types to self-certify and where to open, so margins and player markets arrive on its schedule rather than all at once. The regulatory steps are easier to follow in order, which is what a Polymarket review from Bonus.com does, running from the 2022 order through the 2025 designation and covering where the platform restricts access and how its contracts settle.

The international site and the US app aren't the same product, which is easy to forget when both carry one name. Pew's own count, for instance, folds them together.

Player Contracts Are Where The CFTC Drew Its Line

Move from the team to the individual and the regulator's tone changes. The same proposal that defended game outcomes named sports contracts it considered likely to be found contrary to the public interest, and so prohibited.

ESPN's report on the 267-page proposal listed the occurrence or severity of injuries, refereeing decisions, fights during games and youth sports among them, and said it would also likely bar "discrete-action contracts involving specific participants," better known as in-game props.

The Commission explained why. It wrote that a contract is more troubling when "insight into the underlying event is highly concentrated," giving a single individual as its example, along with people barred by law from trading. A player often knows before anyone else whether he'll suit up. A trainer knows about the hamstring before the injury report does.

Kalshi has already tested where that line falls. Legal Sports Report found it listing contracts ahead of NFL Week 1 on whether individual athletes would play, which avoids asking about an injury directly but trades on much the same information. The NBA had already asked the CFTC to rule out trades on officiating, injuries and fan actions, and the NFL made a similar request of the operators.

The comment period closed on July 27, and no final rule has been published as of late September, so the line is proposed rather than drawn.

An MVP Contract Keeps Trading After The Ballots Are Cast

Season-long contracts look harder for any one insider to exploit, because no single play decides them. They also stay open for months, so the price absorbs every injury, trade and benching along the way. Awards complicate that picture. Polymarket's international site, which blocks trading from the US, lists a market on this NFL season's MVP with 29 possible outcomes. It opened in late March and had seen about $1 million traded by this week, when Josh Allen led at roughly 27 cents. Its rules say it resolves on official NFL information, and on credible reporting if needed.

Consider how the last award was decided. The Associated Press said its panel of 50 media members who cover the league finished voting before the playoffs began, with ballots ranking five players on a 10-5-3-2-1 scale. The winner wasn't announced until NFL Honors on Feb. 5. Matthew Stafford took it with 366 points to Drake Maye's 361, a five-point gap across 50 ballots.

For those playoff weeks, the answer existed. Each voter held a fiftieth of it and the accounting firm that tallied the ballots, Lutz and Carr, held the total, while any open market on the award kept moving on public guesses. This describes an exposure, not any known misuse. The CFTC's own test, insight concentrated in very few hands, comes close to describing a sealed ballot, yet awards don't appear among the sports examples ESPN summarized.

Two Appeals Courts Have Given Opposite Answers

Above all of this sits a question nobody has settled: whether federal commodities law or state gaming law governs a contract tied to a game. Earlier this year the Third Circuit, in a Kalshi case against New Jersey, found event contracts are swaps under the CFTC's authority. On Aug. 28 the Ninth Circuit ruled the other way for sports contracts, rejecting Kalshi and Crypto.com's appeal against Nevada's Gaming Control Board. New Jersey asked the Supreme Court to step in on Sept. 2, and a Bank of America note cited by CNBC said the justices might wait until next year.

Polymarket has its own Nevada file. The Gaming Control Board sued early in the year and quickly won a temporary restraining order that covered Super Bowl weekend. A Carson City judge later granted a preliminary injunction blocking Polymarket US from operating in the state, according to the Las Vegas Review-Journal. Minnesota went further and passed an outright ban, which a federal judge halted before it could take effect. Other states are pressing their own cases, so for now a fan's answer turns on which state they're standing in.

The leagues are split as well. The NFL told Sports Business Journal that it isn't considering prediction-market operators for its sponsorship designations, while the NHL signed agreements with both Kalshi and Polymarket in 2025, The Block reported.

Sponsorship deals, league statements and publisher feeds such as Bonus.com on Instagram all trail the dockets, which is where these questions will actually be decided.

So when a contract promises something beyond the final score, the useful question isn't how clever it is. Ask who already knows the answer, and whether you're one of them.