Compare n' Bet™
Compare n' Bet™
Prediction markets like Kalshi and Novig are a new way to place sports bets in many US states where traditional sportsbooks aren't available. They work differently from sportsbooks, and understanding those differences matters if you want to use them well.
A prediction market is a platform where people trade contracts on the outcome of real-world events. Each contract pays out a fixed amount if the event happens and zero if it doesn't. The price of the contract reflects the market's collective estimate of the probability.
Here's a simple example. A contract that pays $1 if "Team A wins the game" might trade at $0.58. That means the market collectively thinks Team A has a 58% chance of winning. If you buy the contract at $0.58 and Team A wins, you get paid $1, for a profit of $0.42. If Team A loses, your contract expires worthless and you lose the $0.58.
You can also sell contracts, which is essentially betting against the outcome. If you sell a contract at $0.58, you collect $0.58 up front. If Team A loses, you keep it. If Team A wins, you owe $1 (losing $0.42 net).
The structural difference is that prediction markets are peer-to-peer. You're not betting against the house. You're betting against other traders on the platform. The platform takes a small fee on completed trades but doesn't set the prices or benefit from either outcome.
Sportsbook prices always include vig, the house margin. A standard sportsbook spread price might be -110 on both sides, which is about 4.5% vig. Prediction market prices, by contrast, reflect actual supply and demand among traders. The effective "vig" on an efficient prediction market is often much smaller, sometimes as low as 1-2%.
In theory, this means prediction markets should offer better prices than sportsbooks. In practice, it depends on the specific market, how much volume is trading, and how many sharp traders are participating.
The big catch with prediction markets is liquidity. A market with lots of trading volume (say, an NFL moneyline for a popular team on a Sunday afternoon) will have tight pricing and easy entry/exit. A market with low volume (say, a niche prop bet) might have wide spreads and difficulty getting filled at a reasonable price.
Sportsbooks don't have this problem. Their prices are always there at the stated number, regardless of how many people are betting. Prediction markets require an actual counterparty for you to trade against.
Kalshi is the most-used prediction market platform in the US. It's regulated by the CFTC (Commodity Futures Trading Commission), which classifies sports event contracts as event derivatives rather than gambling. This regulatory framework has let Kalshi operate in all 50 US states, including states where traditional sports betting is not legal.
Kalshi offers contracts on major sports (NFL, NBA, MLB, NHL, UFC, soccer), as well as non-sports markets (politics, economics, weather, entertainment). Sports-specific contracts include moneylines, spreads, totals, and some prop-style markets. The contracts are settled based on official outcomes.
Novig positions itself as a "no-vig sportsbook" (hence the name). It uses an order-book model where users bet against each other at specified prices. In practice, Novig operates similarly to a prediction market, with users providing liquidity to each other rather than betting against a traditional sportsbook.
Novig has operated in some states but has faced regulatory scrutiny similar to other event contract platforms. Availability has varied over time. Check their current operating status before assuming you can bet there.
Polymarket is the largest prediction market globally but operates outside the US regulatory framework. It uses cryptocurrency for deposits and withdrawals. As of 2026, US residents are restricted from using Polymarket due to a CFTC settlement. Non-US users can and do use it, including for sports contracts.
As noted, prediction markets have lower effective vig. A spread that's -110 on both sides at a sportsbook might be trading at effective odds of -103 on both sides at a prediction market. That's a meaningful difference over time.
Sportsbooks have lots of casual "public" money, which tends to push lines in predictable ways (toward big favorites, popular teams, overs). Prediction markets have a higher proportion of sharp, model-driven traders. Lines on prediction markets tend to reflect a more balanced, informed view earlier than sportsbook lines do.
In practice, this can go either way. If the public is correct on a given bet, sportsbook lines might be sharper because they've moved to reflect the public's correct view. If the public is wrong, prediction market lines will reflect the sharper take while sportsbooks are still shading for public money.
Popular markets on prediction markets (big NFL games, NBA finals) can have significant liquidity. Unpopular markets (obscure college games, lower-league soccer) often have almost no liquidity, with wide bid-ask spreads that make them effectively unbettable.
Sportsbooks don't have this problem but also don't give you the benefit of sharper pricing. The tradeoff is real.
The biggest practical use case for most bettors. If you live in California, Texas, Florida, or any state where traditional sports betting is still not available, prediction markets are often the only legal, regulated way to have action on games. Kalshi in particular has made this accessible.
Sunday NFL moneylines on popular teams, major NBA games, Champions League finals, Super Bowl markets. Anywhere the volume is high, prediction market prices often beat sportsbook prices by a meaningful amount.
Prediction markets let you sell contracts, which is essentially betting against the outcome. You can create a position that's equivalent to betting the under or fading a favorite at a specific price, sometimes at better odds than the sportsbook's corresponding side.
Player props, alternate lines, same-game parlays, team totals. Sportsbooks have dozens of prop markets for every NFL game. Prediction markets cover a fraction of those and often at low liquidity. For anything beyond major game lines, sportsbooks still dominate.
Live betting on prediction markets is possible but not well-developed. Sportsbooks have sophisticated live betting infrastructure with constant line updates. Prediction markets for live events exist but often have slow updates or low liquidity during games.
Sportsbooks offer constant promotions: boosts, free bets, parlay insurance, deposit matches. Prediction markets generally don't. If you're hunting promotions, traditional sportsbooks are the only option.
This is an actively evolving area. Prediction markets exist in a legal gray area in many states. The CFTC regulates event contracts at the federal level, but individual states have their own gambling laws that sometimes conflict with federal regulation.
As of April 2026, Kalshi operates in all 50 US states under its CFTC registration, though some states have challenged this and may restrict availability in the future. Novig's availability has varied state by state and should be verified before use. Expect continued legal disputes and evolving regulations throughout the next few years.
For the current status in your state, check our state-by-state legalization guide.
Before you trade, look at the buy price and the sell price. The difference between them is effectively the spread. If it's tight, the market is liquid and pricing is likely sharp. If it's wide, you might be paying too much relative to the true price.
If you're trying to bet a small college football game on Kalshi and the only available price looks 15 cents worse than what a sportsbook would offer, skip it. The convenience isn't worth the bad price.
Prediction markets usually quote prices in cents (e.g., $0.58 for a contract that pays $1). Sportsbooks use moneyline odds. To compare, convert: a $0.58 contract implies 58% probability, which is roughly equivalent to a -138 moneyline. A $0.45 contract implies 45% probability, roughly a +122 moneyline.
Prediction markets charge small trading fees. These are usually built into the displayed prices, but some platforms charge them separately. Read the fee schedule before trading serious money.
Not always. In low-liquidity markets, prediction markets can have effectively wider spreads than sportsbooks. In markets where the public is sharper than the prediction market crowd, sportsbook lines can be tighter. Shop across both.
The business model is genuinely different. Prediction markets match buyers and sellers without taking positions. Sportsbooks set odds and profit when their customers lose. That structural difference shows up in pricing, available markets, and regulation.
Arbitrage is theoretically possible but practically difficult. The price differences are rarely large enough to clear the combined fees, and by the time you execute both sides, prices often move. True arbitrage opportunities are rare and fleeting.
This depends entirely on your state. In some states, prediction markets are clearly legal. In others, their status is contested. Don't assume they're risk-free from a legal standpoint just because they're regulated by a federal agency.
The smart play for bettors with access to both prediction markets and traditional sportsbooks is the same as the smart play for any sports bettor: shop prices before you bet. Check what the price is at your usual sportsbooks. Check Kalshi or Novig. Take the best price.
Compare n' Bet tracks both prediction market prices and traditional sportsbook prices (where available), giving you the full picture in one place. For moneyline bets in particular, the price differences between platforms can be significant, and the side with the better price often changes night to night.
Prediction markets are a real, legitimate alternative to traditional sportsbooks for many American bettors. They offer lower effective vig, genuine peer-to-peer trading, and legal access in states where regular sportsbooks don't operate.
They aren't a cure-all. They have liquidity limits, fewer available markets, and their own regulatory uncertainty. But for major-market bets, particularly moneylines on popular games, they're often the best-priced option.
Treat them as another tool in your kit. Check their prices alongside traditional sportsbooks. Take whichever offers the best deal on the bets you were planning to make. That's line shopping, and it works the same way regardless of whether the platform calls itself a sportsbook or an event contract exchange.
This guide is for informational purposes only. Compare n' Bet does not offer gambling advice or predictions. The regulatory status of prediction markets is actively evolving and may have changed since this guide was last updated. Please gamble responsibly.