709 words, 4 minutes read time.
Liquidity and fee structure vary significantly between Kalshi, Polymarket, and PredictIt. The comparison below provides an overview of their 2025 trading environments, highlighting costs and market depth.
Liquidity
Liquidity in prediction markets is how easily and cheaply you can buy or sell contracts without significantly moving the price. High liquidity usually means tight bid-ask spreads, deep order books, and sufficient trading volume so that prices react quickly to new information and reflect a broad set of views.
Why Liquidity Matters
- Fairer prices and better forecasts: In liquid markets, even moderately sized trades barely move the odds, so prices are more likely to be accurate aggregations of many traders’ information instead of the opinion of a few.
- Lower trading costs and slippage: With tight spreads and deep liquidity, traders can enter and exit positions at prices close to the quoted odds, reducing hidden costs beyond explicit platform fees.
- Easier risk management: High liquidity lets you adjust or close positions quickly if news breaks or your view changes, rather than being “stuck” without a counterparty.
- Kalshi: Kalshi offers solid liquidity, particularly for popular economic and political events, thanks to a maker-taker model that incentivizes market making with rebates of up to 1% of trade volume. Liquidity is concentrated in trending markets and amplified by various incentive programs for both makers and high-volume traders.
- Polymarket: Polymarket stands out for its large pools of user-provided liquidity, especially in hot or viral markets. However, market depth can fluctuate quickly, and some activity has been attributed to “artificial” volume due to wash trading. Overall, liquidity in primary markets is high for a decentralized platform.
- PredictIt: Historically, PredictIt’s liquidity was limited by strict per-contract and per-market caps, but recent regulatory changes have enabled higher limits and broader market offerings. Still, liquidity does not reach the levels seen on Kalshi or Polymarket, with political markets being the most liquid.
Fees
(as of November 2025)
| Platform | Trading Fee Structure | Deposit/Withdrawal Fees |
|---|---|---|
| Kalshi | $0.01–$0.02 per contract, price-dependent, capped at about $1.75 per 100 contracts; no account fee | 2% on card deposits, $2 withdrawal (ACH free), possible crypto network fees |
| Polymarket | 0.2% liquidity provider fee per trade, with transaction/gas fees on crypto transfers | Gas fees only; Polymarket does not add extra |
| PredictIt | 10% profit fee when you sell shares for gain; 5% withdrawal fee | 5% withdrawal, no deposit fee |
3 Key Takeaways
- Kalshi is more cost-effective for frequent traders due to per-contract fees and capped commissions, and it has deeper liquidity supported by incentives.
It uses market makers and incentive programs (rebates, volume rewards) to keep spreads tight and depth reasonable in its core macro and political markets, so liquidity is often strongest where institutions and serious hedgers participate. That makes it attractive if you care about entering and exiting larger positions with minimal price impact. - Polymarket uses a simple fee model that primarily benefits liquidity providers, but end users mainly notice network fees, with trade costs around 0.2% and substantial liquidity in viral markets.
It runs on an automated market-maker and community liquidity model, which tends to produce very high liquidity in viral or news-driven markets but thinner depth in niche ones. For traders, that means liquidity is excellent on headline events, but you must inspect each market’s volume and pool size before sizing a trade. - PredictIt remains expensive for profitable trading due to the 10% take on profits, and liquidity is most robust for popular political contracts. However, recent changes have modestly improved depth for high-interest events.
It has historically had lower liquidity, in part because of regulatory position limits and a narrower user base, so spreads can be wider, and it can be harder to move in or out of size without shifting prices. When comparing platforms, PredictIt is better suited to small, slower-moving political speculation than to frequent, size-sensitive trading.
In short, when comparing Kalshi, Polymarket, and PredictIt, liquidity is crucial because it determines how reliable the odds are as forecasts and how costly or risky it is for you to trade those odds in practice. This comparison makes Kalshi and Polymarket more attractive to heavy users or to those seeking lower fees and a deeper order book. At the same time, PredictIt maintains its niche in regulated, US-based political betting despite higher trading costs.
Thanks for supporting hobbyjoy.com by using our links when you sign up. It lets us keep bringing you the best intel on where to get your prediction fix.
Now forecast something wild!
