Prediction Markets in 2025: Data, Stats & Key Trends

The numbers from 2025 are hard to believe. A niche corner of the internet that barely registered a few years ago processed over $63 billion in trading volume in a single year. This is the definitive data breakdown.

The global prediction market industry grew 4× in 2025 alone, hitting $63.5 billion in total notional trading volume, up from roughly $15.8 billion in 2024.

And that’s before factoring in the Paradigm research note flagging that some Polymarket volumes may be double-counted. Even with that caveat, the growth is structural, broad-based, and undeniable.

To understand just how fast this happened: in 2022, total industry volume was approximately $0.5 billion. In three years, the sector grew 127×.

Who Controls the Market?

Two platforms now dominate the entire space. Polymarket and Kalshi together accounted for approximately 97.5% of total prediction market trading volume in 2025. No other competitor comes close. The duopoly is real, reinforced, and growing stronger.

Kalshi processed 97 million transactions in 2025 and set a single-day record of $381.7 million on December 21. Polymarket’s October 2025 saw 477,850 active monthly traders, its single largest user month.

The Category Nobody Expected to Win

Every major headline in 2025 credited elections and politics as the driver of prediction market growth. The data says something very different.

Technology & Science markets grew 1,637% year-over-year, and Economics markets followed at +905%. Politics grew only 43%, the slowest category despite receiving the most press coverage.

This is a significant signal for traders and platform builders alike. The post-election hangover many feared didn’t collapse the industry because the growth had already diversified. Macro events, Fed rate decisions, jobs reports, inflation data, are becoming the new battleground for liquidity.

Open interest in economics-focused markets grew 7× across 2025, and social/tech OI grew 6×, compared to just 2.2× for politics.

The Q4 Breakout: What Actually Happened

Both platforms were flat through the first eight months of 2025. Monthly volumes for Polymarket hovered between $0.8–1.2B from January to August. Kalshi was in a similar range. Then October hit, and everything changed.

Polymarket’s monthly volume jumped from $1.43B in September to $3.02B in October, a 110% single-month increase. Kalshi went from roughly $0.85B to an estimated $4.4B the same month, then $5.8B in November and a record $6.38B in December.

The catalysts: ongoing Trump administration trades, U.S. economic policy uncertainty, a sports betting wave on Kalshi, and Polymarket’s reported POLY token airdrop speculation driving retail inflows.

Single prediction markets on Polymarket drew $10–$20 million in individual contract liquidity during peak October weeks. – Forbes

Kalshi’s Institutional Moment

Kalshi isn’t just growing, it raised a $1 billion Series E in 2025 led by Paradigm, with participation from Sequoia, Andreessen Horowitz, and ARK Invest, valuing the company at $11 billion. That’s up from a $5 billion valuation in October 2025, a 120% valuation jump in under three months.

The capital unlocked critical partnerships. Kalshi integrated with Robinhood and Webull, instantly expanding its distribution to tens of millions of U.S. retail brokerage users.

A partnership with the CME Group added institutional credibility. Sports betting, particularly NFL championship contracts which generated over $65.8 million in single-contract traded volume, accounted for 75% of Kalshi’s total 2025 activity.

Polymarket Goes Regulated

The biggest structural shift for Polymarket in 2025 was regulatory. After years of being geoblocked from the U.S., Polymarket acquired QCEX, a registered derivatives exchange, in late 2025, effectively giving it a path to CFTC-compliant U.S. access.

U.S. entry remains invite-only and restricted through intermediaries as of early 2026, but the door is open for the first time since the 2022 settlement.

This matters enormously for liquidity. The U.S. represents the largest pool of retail and institutional trading capital, and Polymarket’s crypto-native global model is already competitive, bringing that firepower into the domestic market would fundamentally alter the duopoly dynamics.

Liquidity & Open Interest Deep Dive

Both platforms sat at equal open interest (~$400M each) as of January 31, 2026, making them genuinely competitive at the top of the liquidity stack.

Kalshi’s edge in raw volume comes primarily from its sports vertical, a category Polymarket barely competes in.

The Volume Inflation Caveat

Any honest analysis of Polymarket’s numbers must flag the double-counting problem.

In December 2025, Paradigm published a detailed technical breakdown showing that Polymarket’s NegRisk market structure, which allows multi-outcome markets, causes certain on-chain trackers to record both sides of a trade as independent transactions.

The result: widely cited volume figures may significantly overstate actual economic activity.

This doesn’t mean Polymarket is fraudulent. The price accuracy and crowd-sourced probability signals remain reliable. But it does mean Kalshi’s $23.8B figure, derived from cleaner fiat accounting, is a more apples-to-apples measure of real economic volume.

The Risk Register for 2026

Growth at this speed comes with real risks that traders and observers should track:

• Wash trading peaked at ~60% of some reported Polymarket volumes in 2024, according to CertiK analysis, a significant concern for market integrity

• State-level regulatory warfare: Kalshi is in active litigation with Arizona, Illinois, and other states that classify its sports contracts as unlicensed gambling.

• Security vulnerabilities: A Magic Labs security breach in December 2025 exposed some Polymarket wallet infrastructure

• Incentive dependency: A portion of volume growth is directly tied to airdrop speculation and token incentives, removing these could deflate headline numbers

• Robinhood’s own entry: Robinhood has signaled it may launch a competing prediction market product, which could fragment Kalshi’s retail distribution moat

What 2026 Looks Like

The trajectory heading into 2026 is extraordinary. At February 2026’s combined run rate of $16.8B/month ($7B Polymarket + $9.8B Kalshi), the industry is on pace for $200B+ in annual volume, with some forecasts reaching $325B if growth holds. CNBC cited an industry report projecting prediction markets could hit $1.1 trillion by 2030.

The longer-term structural bet is on economics and macro becoming the dominant category, overtaking sports and politics as institutional players bring serious capital to Fed decisions, jobs reports, and geopolitical event contracts.

That’s the market segment where prediction markets most resemble traditional financial derivatives, and where the most sophisticated money will eventually concentrate.

The Trader’s Bottom Line

2025 wasn’t just a good year for prediction markets. It was the year the asset class proved it wasn’t going away.

The combination of Kalshi‘s institutional infrastructure and Polymarket‘s global liquidity has created a genuine two-sided market ecosystem that is starting to attract the same serious attention as early crypto exchanges or sports betting platforms at their inflection points.

For traders on tradetheoutcome.com, the practical implication is clear: the markets are deeper, the odds are more efficient, and the competition from sophisticated participants is increasing.

This means edge is harder to find, but the markets where it exists are bigger, more liquid, and more valuable than ever before.

Data sources: KalshiData (X/Twitter), Dune Analytics (filarm dashboard), FalconX Research (Feb 2026), Forbes (Boaz Sobrado, Dec 2025), Yahoo Finance/The Block, CNBC, Paradigm Research, AInvest, KuCoin. Monthly Q1–Q3 2025 figures are estimated from confirmed annual totals and available data points. All figures in USD notional volume. This article is for informational purposes only and does not constitute financial advice.