Polymarket and Kalshi are the two largest prediction markets in the world, and in 2026 both are regulated by the CFTC as Designated Contract Markets. The practical difference is not legitimacy — it's mechanics. Kalshi is a USD-funded exchange built for a traditional-finance onboarding experience, while Polymarket settles on-chain in stablecoins and carries a deeper, faster-moving catalog of global markets. Which one is "better" depends on how you want to fund your account and what you want to trade.

This guide compares them on the things that actually change your experience and your returns: how each is regulated, what each charges, how you deposit and withdraw, what markets they list, and how a market resolves once the event is over. Every fee number and resolution detail below is pulled from each platform's official documentation, not from a marketing page.

---

The Short Answer

• Both are CFTC-regulated. Kalshi has held Designated Contract Market (DCM) status since November 2020; Polymarket re-entered the U.S. as a CFTC-regulated DCM (operated by QCX LLC) in December 2025.
• Funding is the biggest split. Kalshi takes USD via bank/ACH/wire; Polymarket settles on-chain in a USD-pegged stablecoin.
• Fees use different formulas. Both peak near a 50¢ contract, but the curves and rates differ — details below.
• Polymarket has the broader, faster global catalog; Kalshi has the deeper U.S.-regulated catalog including weather and economics.
• Resolution differs philosophically. Kalshi resolves centrally as the exchange; Polymarket resolves through the UMA Optimistic Oracle, a decentralized propose-and-dispute process.

If you're outside the U.S. or already comfortable holding stablecoins, Polymarket's depth and speed are the draw. If you want dollar deposits and a brokerage-style experience, Kalshi is the cleaner fit.

---

Regulation and Legal Status

This is the question most people get wrong: as of 2026, both platforms operate under U.S. federal oversight.

Kalshi secured Designated Contract Market (DCM) approval from the CFTC on November 4, 2020 and has been federally regulated since. It is registered as a DCM and, through an affiliate, as a Derivatives Clearing Organization (DCO). Kalshi also prevailed in litigation against the CFTC over election-related event contracts.

Polymarket spent a period unavailable to U.S. users, then re-entered the market. It acquired a CFTC-regulated derivatives exchange (QCEX, July 2025) and, following an amended CFTC order of designation, launched Polymarket US — operated by QCX LLC — as a CFTC-regulated Designated Contract Market in December 2025.

The nuance: Polymarket runs a U.S. regulated venue and a separate global, crypto-native venue. Kalshi operates a single regulated U.S. exchange. State-level friction still exists for the category — for example, several states have raised licensing challenges around event contracts — so check what's available in your jurisdiction before funding either account.

---

Fees: How the Two Formulas Actually Work

Both platforms charge fees that peak when a contract trades near 50¢ — the point of maximum uncertainty — and shrink toward the extremes. But the formulas are different, and that difference changes which platform is cheaper for a given trade.

Polymarket's fee

Polymarket charges a taker fee in stablecoin at the moment your order matches. Makers (resting limit orders that add liquidity) pay nothing. Per Polymarket's official documentation, the formula is:

fee = shares × price × feeRate × (price × (1 − price))^exponent

For sports markets created on or after March 30, 2026, the feeRate is 0.03 and the exponent is 1. Polymarket's own worked example: 100 shares at 50¢ → 100 × 0.50 × 0.03 × (0.50 × 0.50) ≈ $0.38 — at most 0.75% of what you spend, and only at the 50¢ midpoint. Other categories carry their own rates (crypto runs the highest at 0.07). Geopolitical and world-events markets are fee-free for both sides. Sell orders are not subject to taker fees, and the minimum charged fee is 0.0001 pUSD.

Kalshi's fee

Kalshi uses a per-contract taker fee with a comparable bell-shaped curve. The general taker formula is:

taker fee = 0.07 × C × (1 − C)   (per contract, C = contract price)

This peaks at a 50¢ contract: 0.07 × 0.50 × 0.50 = 1.75¢ per contract (so $1.75 on 100 contracts) — a midpoint fee Kalshi itself cites, and one it has halved on select series like its S&P 500 and Nasdaq-100 markets. At 10¢ it falls to about 0.63¢, and near 1¢ it's a fraction of a penny. Kalshi also applies maker fees on some markets — charged on resting limit orders only when they execute, at reduced rates per its published fee schedule.

What this means in practice

Both schedules reward you for two things: being a maker (resting liquidity) instead of a taker, and trading away from the 50/50 midpoint where the fee term price × (1 − price) is largest. The shapes differ in one subtle way: Kalshi's per-contract dollar fee is symmetric around the midpoint (a 30¢ contract costs the same as a 70¢ one), while Polymarket's fee is symmetric as a share of what you spend.

For a deeper breakdown of Polymarket's per-category rates and maker rebates, see our dedicated guide to Polymarket fees explained.

Note on deposits: Kalshi charges nothing for ACH and wire transfers but applies up to a 2% processing fee on debit-card deposits. Polymarket itself charges nothing to deposit or withdraw; third-party on-ramps and network gas can apply.

---

Funding: USD vs Stablecoins

This is the difference most new users feel first.

Kalshi funds in U.S. dollars. You deposit via bank transfer, ACH, or wire (free), or debit card (up to a 2% fee). Withdrawals go back to your bank. It behaves like a brokerage account.

Polymarket settles on-chain. Your balance is a USD-pegged stablecoin, and trades settle on Polygon. That means no bank intermediary and near-instant settlement, but it also means you need to be comfortable with a self-custody or wallet-based flow. If you've never held a stablecoin, there's a small learning curve — though tools that abstract the wallet layer remove most of it.

This is also where third-party platforms matter. Trading Polymarket through FrenFlow, for example, keeps funds in your own self-custody wallet (via Privy embedded wallets) while removing most of the crypto friction, and it works across the web app and Telegram.

---

Markets and Categories

Both platforms cover politics, economics, sports, crypto, and culture. The catalogs diverge in breadth and speed.

Kalshi is known for instruments like its FOMC-meeting market chains and a strong weather and economics catalog — categories that benefit from its regulated U.S. footing. Polymarket tends to list global and breaking-news events faster and carries the deeper crypto-native order books. Together, the two platforms accounted for the overwhelming majority of global prediction-market volume in 2025.

---

How Markets Resolve

When the event is over, someone has to declare the winning outcome and pay it out. This is where the two platforms differ philosophically.

Kalshi resolves centrally. As the regulated exchange, Kalshi determines the outcome based on the market's stated resolution source.

Polymarket resolves through the UMA Optimistic Oracle, a decentralized propose-and-dispute system. Anyone can propose the winning outcome by posting a bond (typically $750 in pUSD per Polymarket's documentation). The proposal is assumed correct unless disputed within a 2-hour challenge window. If disputed, the case can escalate — ultimately to UMA's Data Verification Mechanism (DVM), where token holders vote. Undisputed markets resolve in roughly 2 hours; disputed cases can take 4–6 days.

The trade-off: Kalshi's centralized model is faster and simpler but relies on the exchange; Polymarket's oracle model is transparent and permissionless but can occasionally produce contested resolutions on ambiguous markets. If you trade Polymarket, read the resolution rules on each market before you enter — the edge cases are spelled out there.

---

Which Should You Use?

There's no single winner — it depends on your priorities:

• Choose Kalshi if you want USD deposits, a brokerage-style experience, and U.S.-regulated economics, weather, and sports markets with central resolution.
• Choose Polymarket if you want the deepest, fastest-moving global catalog, on-chain settlement, and you're comfortable holding stablecoins.
• Use both if you want to compare odds across venues — the same real-world event is often priced slightly differently on each, which is the basis of prediction-market arbitrage.

Many serious traders run accounts on both and route each trade to whichever venue offers the better price and lower fee for that specific market. FrenFlow supports trading across Polymarket, Kalshi, and Predict.fun from one interface, so you can follow the same proven wallets and compare markets without juggling three apps.

---

Trading Both on FrenFlow

The fees, regulation, and resolution above belong to Polymarket and Kalshi — they apply wherever you place the order, because the trade settles on each platform's own infrastructure. What FrenFlow adds is everything around the trade: a unified interface across Polymarket, Kalshi, and Predict.fun; a traders leaderboard ranked by verified on-chain PnL; and the ability to copy proven wallets in the same block they trade, with your funds in your own self-custody wallet. There's no subscription — you pay only the standard per-trade fee on top of each platform's own fee.

If you're deciding where to start, fund matters most: pick the platform whose deposit method you'll actually use, then let the markets and fees guide each individual trade. For the automation layer on top, see our guide to the best copy trading bot for Polymarket.

---

Frequently Asked Questions

Is Polymarket or Kalshi better?

Neither is universally better. Kalshi is better for U.S. users who want USD bank deposits and a brokerage-style, centrally-resolved experience. Polymarket is better for traders who want the deepest, fastest-moving global catalog, on-chain settlement in stablecoins, and decentralized resolution. Both are CFTC-regulated Designated Contract Markets in 2026.

Are both Polymarket and Kalshi legal and regulated?

Yes. Kalshi has held CFTC Designated Contract Market status since November 2020. Polymarket re-entered the U.S. as a CFTC-regulated DCM, operated by QCX LLC, in December 2025. Availability can still vary by state, so check your jurisdiction before funding either account.

Which has lower fees, Polymarket or Kalshi?

Both charge taker fees that peak near a 50¢ contract and shrink toward the extremes. Kalshi's general taker fee is 0.07 × price × (1 − price) per contract, peaking at 1.75¢ at 50¢. Polymarket's fees vary by category — sports is the lowest at a 0.03 feeRate (at most 0.75% of your spend), crypto the highest at 0.07 — and its geopolitical and world-events markets are fee-free. Makers pay nothing on Polymarket, and on Kalshi maker fees apply only on some markets at reduced rates.

How do I fund a Polymarket vs a Kalshi account?

Kalshi takes U.S. dollars via bank transfer, ACH, or wire (free) or debit card (2% fee). Polymarket settles on-chain, so your balance is a USD-pegged stablecoin on Polygon. Polymarket itself charges no deposit or withdrawal fee, though third-party on-ramps and network gas can apply.

How do markets resolve on each platform?

Kalshi resolves markets centrally as the regulated exchange, based on each market's stated resolution source. Polymarket resolves through the UMA Optimistic Oracle: anyone can propose an outcome by posting a bond (typically $750 pUSD), with a 2-hour dispute window before resolution, escalating to a UMA token-holder vote if disputed.

Can I trade both Polymarket and Kalshi from one place?

Yes. FrenFlow supports trading across Polymarket, Kalshi, and Predict.fun from a single interface, including copying proven wallets from a verified-PnL leaderboard. Your funds stay in your own self-custody wallet, and there's no subscription.