I Tried 5 Prediction Market Platforms After Years of Sports Betting: This Is What I Learned

Prediction markets have gone from a niche corner of the internet to something almost every sports fan has at least heard of in the last year. But “trading a contract on the Chiefs” still feels foreign to most people coming from a traditional sportsbook background. The language is different, the sign-up process is not identical across every platform and the bonus structures do not work like a typical deposit match.

I’ve spent years betting on sports and documented much of that for Oddspedia. Now, I’ve changed things up and walked through the five biggest prediction market platforms right now: Kalshi, Polymarket, Novig, ProphetX and Underdog. I’ve documented everything from the moment you select “sign up” to placing your first funded trade.

My findings are based on my own experience, but I also used each platform’s app and help documentation, current promotional terms and descriptions from other verified users to provide a well-rounded view.

Oddspedia does not have any codes for prediction market sites, so I decided to use Covers.com codes where available to claim the bonuses. I’ve used the platform for years to get my NFL picks, and it is one of the few websites I would place on the same level in terms of trust.

Quick comparison

Terms change frequently across all five platforms, so confirm the live offer in the app before funding your account.

For a more detailed comparison of the two largest platforms, read our Kalshi vs Polymarket guide.

Prediction market platform reviews

Kalshi

The code and bonus

Enter MAX60 during sign-up. It is easy to scroll past if you are moving quickly, so have it ready before you begin. The current offer is structured as trade $25, get $60 in trading credits, applied automatically once you complete the qualifying trade and identity verification.

This is an exclusive bonus through which the code MAX60 gives you $5 more than almost every other code available online. Sports Illustrated is the only place I could find offering the same amount; every other code provides a trade $25, get $55 bonus.

What actually happens when you sign up

Kalshi’s onboarding process is short: enter your email address and the code MAX60, verify your phone number and complete the standard identity checks before funding your account.

Once you are in, the interface looks less like a sportsbook and more like a trading app. Contracts are listed by category, including sports, economics, politics, weather and culture. Each one is priced between $0.01 and $0.99, with that price representing the market’s live estimate of the probability. A contract priced at 58 cents means the market is estimating roughly a 58% chance of that outcome. It settles at $1 if it succeeds and $0 if it does not.

Placing your first trade feels closer to buying a stock than placing a bet. You pick a side, set the number of contracts you want and either take the current price or set a limit and wait for it to fill.

Our Kalshi promo code guide compares the available offers and explains the steps required to claim the bonus.

What stood out

The breadth of its markets is the real differentiator. Kalshi is the only one of the five platforms where you can trade a Federal Reserve interest-rate decision, an election and an NFL game in the same session. The interface is also genuinely clean once you have completed the KYC process.

What to know before joining

Because pricing is probability-based rather than odds-based, it takes a session or two to stop mentally converting everything into its sportsbook equivalent. KYC is also non-negotiable, as there is no way to trade or claim the bonus without completing it first.

Key takeaway: If you want one account covering sports and non-sports events, Kalshi casts the widest net of the five.

Polymarket

The code and bonus

Enter COVERS when signing up for Polymarket US, the CFTC-regulated, dollar-settled version built for American traders. It is distinct from the original global cryptocurrency platform, so make sure you are using the US product.

What actually happens when you sign up

The sign-up process is where Polymarket differs most from the other platforms. The Polymarket promo code COVERS must be entered during registration, not afterwards, as there is no option to add a promotional code once your account exists. After that, you complete the standard KYC process and make a deposit before you can trade.

The trading screen shows a live order book for every contract, and prices move continuously as other users trade. This makes Polymarket feel noticeably more liquid than some of the smaller platforms. Even mid-tier markets tend to have closely matched bid and ask prices rather than a wide gap.

What stood out

Depth. Polymarket consistently has the tightest spreads and most active markets of the five, especially for high-profile events. The order book fills quickly, so a market order rarely feels as though it is chasing a stale price.

What to know before joining

Your username is your referral code, which is a nice touch but also means promotional and referral codes are two completely different mechanics on this platform. Do not confuse them. A Polymarket promo code such as COVERS is a one-time welcome offer entered during sign-up, while a referral code is an existing user’s handle shared for ongoing rewards.

You can still use the code COVERS to sign up and then gain access to the opportunity to earn up to $1,275 through referrals.

Key takeaway: If liquidity and tight pricing matter most to you, Polymarket is the platform to start with.

Novig

The code and bonus

Enter the Novig promo code COVERS during registration. The current offer is deposit $10, get $25 in trade credits, split into five separate $5 credits rather than one lump sum. You will need to place a qualifying $5 trade after making your deposit to activate them, and the credits expire after 30 days. It is therefore worth using them relatively quickly rather than allowing them to sit in your account.

What actually happens when you sign up

Novig is sports-only, with no politics or economics markets, which immediately makes the interface narrower than those of Kalshi or Polymarket. The standout mechanic is “make or take”: you can accept the current market price immediately or post your own price and wait for another trader to match it, as you would on a betting exchange.

Taking the market price fills the order immediately. Setting your own price can mean waiting in the order book for a few minutes during quieter periods before another user takes the other side.

One thing worth knowing before funding an account is that, as of this writing, Novig’s fully regulated CFTC exchange has been approved but has not yet launched. The live product currently runs on a dual-currency sweepstakes model using Novig Coins, which are non-withdrawable, and Novig Cash, which is redeemable subject to eligibility. It is not a red flag, but it is a meaningfully different structure from the straightforward cash-in, cash-out model on Kalshi or Polymarket, so join with a clear understanding of the current setup.

What stood out

The pricing model is the most genuinely exchange-like of the group. There is no house line to beat, only orders placed by other traders. If you have used a betting exchange before, it will quickly feel familiar.

What to know before joining

The sweepstakes-style currency setup requires more careful reading of the terms before you fully understand how funds move. Its credits also expire after 30 days, which is a shorter window than most of the other bonuses covered here.

Key takeaway: Novig is best suited to sports-focused traders who specifically want exchange-style, set-your-own-price mechanics.

ProphetX

The code and bonus

Enter the ProphetX promo code COVERS during sign-up. The current offer is trade $50, get $75 in bonus funds, with a minimum deposit of $10 required to qualify. You then have 45 days to use the bonus funds once they arrive, providing noticeably more time than Novig’s 30-day window.

What actually happens when you sign up

The onboarding process follows the now-familiar exchange pattern: enter your account details, complete identity verification and a geolocation check, link a payment method, deposit and trade.

ProphetX distinguishes itself through its fully visible order book, which shows exactly how much liquidity is available at each price point before you commit. This makes it easier to judge whether you are receiving a fair fill or should post your own price instead. You can also choose “Quick Trade” for an immediate fill at the best available price if you would rather not wait for a custom order.

Its fees also work differently from a typical vig. Rather than incorporating a margin into the price, ProphetX charges a commission on net winnings, commonly cited at around 2% on straight trades, with reduced or no commission on certain parlay-style entries. That is a genuinely different cost structure from a sportsbook’s built-in margin, and it is worth understanding before you begin trading in volume.

What stood out

The order-book transparency. Being able to see the depth available at each price before trading is a small feature that makes a real difference once you are placing more than a couple of trades each week.

What to know before joining

State availability is the widest of the sports-focused platforms covered here, with access in 49 states and Washington, D.C. Nevada is the sole exclusion, but always check availability in your state through the app before funding your account, as exchange-based regulation continues to evolve.

Key takeaway: ProphetX is best for traders who want to see the full order book and are comfortable setting a custom price rather than always accepting the price offered.

Underdog

The code and bonus

Enter the Underdog promo code COVERS during sign-up. The current offer is a 50% deposit match worth up to $1,000. This means a $2,000 deposit receives the full match, although a minimum deposit of $10 is enough to qualify for a smaller bonus. Funds typically appear as bonus entries within approximately 72 hours of your deposit clearing.

What actually happens when you sign up

If you have used Underdog’s fantasy product, the interface will feel immediately familiar. That is the platform’s biggest advantage. Underdog now operates two separate products alongside each other: traditional Pick’em, which offers higher or lower player props with multiplier-based payouts, and Prediction Picks, which are genuine event contracts priced between $0 and $1 according to probability and settle at $1 or $0, like contracts on Kalshi or Polymarket.

The two products use completely different rules, and the app clearly shows which one you are using. However, it is worth slowing down during your first session to confirm that you have selected the intended product.

Combo entries combining Prediction Picks with traditional fantasy selections are also available, a mechanic none of the other four platforms offers in quite the same form.

What stood out

Familiarity. If you already have Underdog’s fantasy app on your phone, moving into Prediction Picks involves a much shorter learning curve than starting from scratch on a pure exchange platform.

What to know before joining

Because Pick’em and Prediction Picks are available in the same app but operate under different rules, it is worth double-checking which product you are using before building a larger entry. The multiplier logic of one and the probability pricing of the other are not interchangeable.

Key takeaway: Underdog offers the easiest introduction if you are coming from daily fantasy rather than sports betting or trading.

So which one should you start with?

There is no single correct answer. It depends on what you are trying to do:

• Want the broadest range of things to trade, not just sports? Start with Kalshi.
• Want the deepest and most liquid markets on major events? Start with Polymarket.
• Want true exchange-style, set-your-own-price trading on sports only? Consider Novig or ProphetX. Choose Novig if you do not mind its current sweepstakes-currency setup, or ProphetX if you want full order-book visibility and a wider state footprint.
• Coming from daily fantasy and want the gentlest learning curve? Start with Underdog.

Plenty of traders eventually use two or three of these platforms alongside each other once they become comfortable. The sign-up process requires only a few minutes and a Covers code, so there is little downside to opening more than one account.

FAQs

Do I need a promo code to use these platforms?

No. You can sign up and trade on all five platforms without one. However, none of these codes costs anything extra to use, and they are all currently active Covers codes, so there is little reason to skip entering one.

Are these considered sports betting or trading?

Legally, all five operate as regulated exchanges or event-contract markets rather than traditional sportsbooks, which is why they use terms such as “trade” and “contract” rather than “bet” and “odds”. Contract prices reflect probability rather than payout odds.

Is my bonus real cash?

The structure varies. Most bonuses arrive as trade credits or bonus entries with expiry periods and activation requirements, such as a qualifying trade, a minimum deposit or a playthrough requirement. Check the specific terms for each platform in the app before funding your account.

Can I use more than one of these codes?

Yes. Each platform’s bonus is independent, so there is nothing stopping you from claiming the Covers offer on all five if you plan to use more than one.

Do the bonus amounts ever change?

Regularly. The figures above reflect the offers available at the time of publication, so always confirm the live terms through the relevant app before depositing.

Offers, bonus terms and state availability are subject to change across all five platforms. Always confirm the current details directly with each platform before signing up.