We grade every prediction market on contract variety, fees, payout speed, and promos — then weight them the way an active trader actually would. Updated weekly.
Prediction markets are, by a wide margin, the fastest-growing corner of American sports wagering right now — and they didn’t even really exist as a mainstream category until the last couple of years. Instead of betting against a sportsbook’s odds, you’re trading “yes” or “no” contracts on game outcomes through exchanges regulated federally by the Commodity Futures Trading Commission (CFTC), not by individual state gaming commissions. That distinction is the whole ballgame: it’s why prediction markets can legally operate in California and Texas, where traditional sports betting remains illegal, and it’s also why more than 20 state gambling regulators are actively fighting to shut that loophole down in court.
The growth numbers are genuinely staggering. Combined monthly trading volume on Kalshi and Polymarket rose from under $5 billion in September 2025 to roughly $53 billion by July 2026 — and one industry analysis from Bernstein estimates that year-to-date 2026 sports trading volume on the two platforms has already surpassed the entire $160+ billion in U.S. sports betting handle processed in all of 2025. Sports now account for anywhere from 39% to over 80% of total trading volume depending on the platform, having overtaken politics as the dominant category on both major exchanges.
Hello Rookie grades every prediction market we cover on contract variety, fees, payout speed, and promos, weighting each category the way an active trader actually would rather than the way a casual sportsbook bettor might.
Polymarket is one of the industry’s best all-around prediction markets, with a polished app, an enormous range of markets, and industry-leading liquidity that makes it easy to get in and out of positions. Polymarket’s international platform has historically dominated the space, though its overall global market share has actually fallen — from an estimated 44% in 2025 to roughly 22% year-to-date 2026 — even as its U.S.-facing arm, Polymarket US, has grown rapidly and now represents nearly half of the company’s total volume.
Kalshi is the biggest and most established name in U.S. prediction markets — a CFTC-regulated exchange with the deepest liquidity, the broadest range of payment options, and a fee structure that beats traditional sportsbook vig by a wide margin. Kalshi’s global market share has surged from roughly 35% in 2025 to about 60% year-to-date 2026, and its monthly trading volume exploded from under $1 billion in August 2025 to roughly $40 billion by August 2026. If you only try one prediction market, this is the one to start with.
Novig made the jump from a sweepstakes model to a fully CFTC-regulated exchange, and the move paid off. Its true no-vig, peer-to-peer pricing and fee-free pregame trading make it one of the sharpest values in the prediction market space right now, a real point of differentiation in a category increasingly dominated by two giants.
ProphetX is the sports-purist’s prediction market — a CFTC-regulated exchange built entirely around sports, with true back-and-lay pricing, no-fee parlays, and a commission model that only charges you when you actually win. The tradeoff is liquidity that’s still filling in outside the major sports, but the sports-first design philosophy is a genuine differentiator from broader platforms that split volume across sports, politics, and crypto.
OG, Crypto.com’s entry into prediction markets, runs on the same CFTC-regulated Nadex infrastructure that’s been federally registered since 2004 — making it one of the longest-standing regulatory frameworks in this entire category, even though OG itself is a newer consumer product. It’s polished, easy to fund, and socially engaging, though market-orders-only trading and a thinner order book outside major sports keep it just below the top tier for now.
This isn’t a settled industry — it’s an active legal battleground. In early September 2026, New Jersey filed a petition asking the U.S. Supreme Court to resolve a growing circuit split over whether CFTC-registered prediction markets like Kalshi can offer sports-related event contracts without complying with state gambling laws. The core legal question is whether the 2010 Dodd-Frank Act’s grant of “exclusive jurisdiction” to the CFTC over “swaps” preempts state sports-wagering statutes entirely. A Third Circuit panel ruled 2-1 that it does; the Ninth Circuit reached the opposite conclusion weeks later in a separate case involving Nevada. Robinhood and Crypto.com have since filed their own petition asking the Supreme Court to take up the fight as well. Forty-four states, hundreds of tribal nations, and major casino operators have weighed in against the prediction markets’ position, while the CFTC itself has filed nine separate suits against states to defend its exclusive regulatory authority.
In the meantime, the CFTC has actually been loosening the rules in other ways — a September 2026 “no-action letter” cleared the way for prediction markets to be embedded into more consumer apps, wallets, and platforms without those integrators needing to register as brokers, a move that immediately sent sports betting stocks lower and prompted at least one Native American tribe to announce its own prediction markets app. At the same time, the CFTC has issued new guidance warning platforms to pull back on riskier “mention markets” — bets on what public figures might say — citing manipulation concerns. It’s a genuinely fluid regulatory picture, and we’ll keep tracking it here.
Every platform above is scored on contract variety, trading fees, payout and withdrawal speed, and the strength of new-user promos. Because prediction markets operate differently than traditional sportsbooks — trading contracts rather than placing fixed-odds wagers — we weight our grades the way an active trader would evaluate a new exchange, not the way a casual bettor picks a sportsbook.
Check out our full prediction market reviews for in-depth breakdowns of each platform, or head to our prediction market promo codes page for the latest welcome offers.
Are prediction markets legal in states where sports betting isn’t?
Currently, yes — platforms like Kalshi and Polymarket operate as CFTC-regulated exchanges rather than state-licensed sportsbooks, which is why California and Texas residents can legally use them even though traditional sports betting remains illegal in both states. That said, more than 20 state gambling regulators dispute this legal framework, and the issue may ultimately be decided by the U.S. Supreme Court.
How big are prediction markets compared to traditional sports betting?
By some measures, sports trading volume on Kalshi and Polymarket combined has already surpassed the entire $160+ billion U.S. sports betting handle from 2025, though it’s worth noting that trading volume and sportsbook handle aren’t perfectly apples-to-apples comparisons. Either way, the growth trajectory is remarkable — from under $5 billion in combined monthly volume in September 2025 to over $50 billion less than a year later.
What’s the difference between Kalshi and Polymarket?
Kalshi is U.S.-based and has grown to roughly 60% of global prediction market share in 2026, while Polymarket’s international platform has historically been larger but has seen its overall share shrink as Kalshi’s growth accelerated; Polymarket’s U.S.-facing arm, Polymarket US, has been the fastest-growing part of the company. Sports also make up a different share of volume on each: as much as 80%+ on Kalshi versus closer to 40-50% on Polymarket, which carries more political and crypto trading.
