What Are Prediction Markets? A Beginner's Complete Guide
A plain-English explanation of how prediction markets work, who they are for, and what you need to know before trading your first contract.
Last Updated: May 21, 2026
TL;DR
- ·Prediction markets let you trade contracts on real-world outcomes
- ·Prices reflect the crowd's probability estimate — $0.65 means 65% likely
- ·You can buy OR sell contracts, and exit before the event resolves
- ·CFTC-regulated platforms like Kalshi are legal in most US states
- ·Trading fees erode returns — treat these as speculative, not investments
A prediction market is an exchange where people buy and sell contracts tied to real-world outcomes. The price of a contract at any moment reflects what the crowd collectively believes is the probability of that outcome happening.
If a contract for "Will the Fed cut rates in September?" is trading at $0.72, the market is pricing in a 72% chance of a rate cut. If you think the real probability is higher — say 85% — you buy. If you think it's lower, you sell.
How a contract works
Every prediction market contract resolves to either $1.00 (the outcome happened) or $0.00 (it didn't). That simple mechanic is the foundation of everything.
Say you buy a "Yes" contract for $0.40. Two things can happen:
- The outcome happens — your contract settles at $1.00 and you profit $0.60 per contract.
- The outcome doesn't happen — your contract settles at $0.00 and you lose your $0.40.
You don't have to hold to resolution. If you buy at $0.40 and the price moves to $0.60 — because sentiment shifted, new information came out, or just because more buyers showed up — you can sell and lock in a $0.20 profit without waiting for the event to happen.
What kinds of events can you trade?
The range of markets on regulated platforms has expanded dramatically since 2023. Today you can trade on:
- Politics: election outcomes, congressional votes, presidential approval ratings
- Economics: Fed rate decisions, inflation prints, GDP growth, unemployment reports
- Sports: game winners, season standings, championship outcomes
- Crypto: Bitcoin price levels, ETF approvals, network events
- Science and culture: Oscar winners, weather events, tech milestones
Some platforms specialize. PredictIt is almost entirely politics. Novig and ProphetX are sports-only. Kalshi and Polymarket offer the broadest coverage.
Why do prediction markets exist?
The academic argument for prediction markets is that they aggregate information. When thousands of people with different knowledge and incentives bet real money on an outcome, the resulting price is often a better forecast than any single expert.
Researchers have documented this in elections, corporate earnings, sports, and public health. Polymarket's odds on the 2024 US presidential election were notably more accurate than many polling models months in advance.
For traders, the appeal is simpler: if you have an informational edge — you know something the market doesn't, or you're better at estimating probability — you can profit from it.
Who runs these markets?
In the US, prediction markets that trade real money must be regulated. The primary regulator is the Commodity Futures Trading Commission (CFTC), which treats prediction market contracts as derivatives.
Kalshi, Polymarket, OG.com, and several others are CFTC-registered Designated Contract Markets (DCMs). This means they are subject to federal oversight, capital requirements, and market manipulation rules — similar to a futures exchange, not a sportsbook.
Some platforms operate under state-level frameworks or sweepstakes models instead. These are generally less regulated and not available everywhere.
What does it cost to trade?
Most regulated platforms charge a fee per trade — typically 2–5% of the contract value. Kalshi charges around 3%. PredictIt charges 10% of profits plus a 5% withdrawal fee, which is significantly more expensive.
Polymarket charges no trading fees, but requires cryptocurrency (USDC) to participate, which introduces its own friction and costs.
Fees compound quickly. If you're trading frequently on a platform with 3% fees, you need to be right by a meaningful margin just to break even over time.
Is this gambling?
Legally, CFTC-regulated prediction markets are classified as derivatives contracts, not gambling — a regulatory distinction that determines which laws apply and which states allow them. It does not mean prediction markets are financially safer than gambling, or that your money is more protected from loss.
The speculative risk is real and direct. You are putting money on uncertain outcomes, and that money can go to zero. Some markets — Fed decisions, election outcomes, economic indicators — reward careful probabilistic research. Others are closer to a coin flip. Either way, you can lose everything you put in.
The regulatory label changes the legal framework. It does not change the fact that most retail participants lose money over time. Market makers, institutions, and well-capitalized traders with genuine informational edges are your counterparties. Treat any capital you allocate here as money you can afford to lose entirely.
Is it legal where you live?
CFTC-regulated platforms are legal in 44+ US states. Restricted states include Illinois, Maryland, Nevada, Ohio, Arizona, and a handful of others — the list changes as regulations evolve. Each platform publishes a current state availability list you should check before signing up.
Crypto-based platforms like Polymarket have different state restrictions and their own compliance requirements for US users.
Should you start trading?
Prediction markets are genuinely interesting if you enjoy thinking probabilistically about current events. They are also genuinely risky if you approach them as a reliable income source.
A reasonable first step is to pick a well-regulated platform, deposit a small amount — $20 to $50 — and trade a few markets you already follow closely. The goal is to understand the mechanics before putting more money at risk.
The platforms covered in this guide represent the full spectrum from CFTC-regulated exchanges to crypto-native global markets. Read the platform reviews to find the right fit before you deposit anything.
Frequently Asked Questions
Responsible Participation
Prediction markets involve real financial risk. Trading fees erode returns regardless of outcome. Information asymmetry disadvantages retail participants relative to professional traders. Never participate with money you cannot afford to lose. Treat prediction markets as speculative instruments for entertainment or civic engagement — not as an investment or income strategy.
If speculative trading is causing financial or personal problems, call the National Problem Gambling Helpline: 1-800-522-4700 (free, confidential, 24/7).