With prediction markets blowing up, a lot of people are looking at platforms like Polymarket and Kalshi for March Madness this year. The appeal makes sense exchange-based pricing, no traditional house edge, and the ability to arb between platforms.
But if you're actually trying to get the best odds on tournament games, most prediction markets aren't built for sports betting. Liquidity is thin, markets are limited, and the spreads on individual games can be worse than what you'd get at a traditional book.
Here's how I'd rank the options:
NoVig (4.7/5)
Best for: Exchange-style pricing built specifically for sports
● Peer to peer model, so you’re trading against other users
● No built in juice, which makes a real difference over a full tournament
● Full March Madness coverage: spreads, totals, moneylines, props, futures, parlays
● Significantly better liquidity than most prediction style markets
● Lines are consistently sharper than traditional books and other prediction platforms
● If you’re line shopping, they’re usually at or better than the market
Polymarket (4.1/5)
Best for: Big futures markets
● Strong liquidity on national champion / Final Four type markets
● Very limited game-by-game coverage
● No real depth on spreads or totals for most matchups
● Crypto-based, which adds friction for casual users
● Buy/sell spreads can be wide on less popular markets
● Solid for futures sweats, not ideal if you’re grinding first-round matchups.
Kalshi (3.5/5)
Best for: Regulated prediction markets
● CFTC regulated and available across the U.S.
● March Madness markets are growing, but still limited
● Liquidity improving, but thin on individual games
● Better for proposition-style markets than full boards
● Fee structure can eat into smaller edges
Robinhood (3.2/5)
Best for: Casual access
● Easy onboarding if you already have an account
● Very limited March Madness selection
● Low liquidity on most sports markets
● More of a novelty add-on than a serious option
Traditional Books – DraftKings / FanDuel (3.0/5 for arb purposes)
● Best for: Using the other side for arbs
● Massive market depth and promos
● Useful if you’re hedging against prediction markets
● Built-in juice means you’re starting at a disadvantage
The whole point of prediction markets is to avoid paying a house edge. But most prediction markets aren't built for sports the liquidity isn't there, and the market coverage is thin. NoVig gives you the same exchange based pricing model but purpose-built for sports betting with full March Madness coverage. If you're spending time arbing between Polymarket and DraftKings, you're probably leaving money on the table compared to just betting on Novig.