Kalshi vs Polymarket US
Kalshi
Regulated exchange · USD · United States
8.0 out of 10, editor score
- +Regulated: CFTC-designated contract market — Kalshi (CFTC DCM register: “Designated”, 3 November 2020)
- +$10 minimum deposit
- +7 market categories
Polymarket US
Regulated exchange · USD · United States
— out of 10, editor score
- +Regulated: CFTC Designated Contract Market: QCX LLC d/b/a Polymarket US (designated 9 July 2025; amended order 25 Nov 2025 permits FCM-intermediated access)
- +Free withdrawals
- +7 market categories
Verdict
The two biggest names in regulated US prediction markets, both CFTC-designated exchanges trading in dollars. Kalshi has the longer record — designated in November 2020 — and an international customer base; Polymarket US is newer, US-only, and brings Polymarket’s market style onto a regulated exchange. Their taker fees follow almost the same formula.
Row by row
The edge on each row is marked. Built automatically from the platform records, so it never drifts from the reviews — rows that describe rather than rank, like jurisdiction or market categories, say “no edge” instead of picking a side.
| Criterion | Kalshi | Polymarket US | Edge |
|---|---|---|---|
| Overview | |||
| Editor Score | 8/10 | Not rated | No edge |
| Type | Regulated exchange | Regulated exchange | No edge |
| Launched | 2021 | — | No edge |
| Mobile apps | iOS, Android | iOS, Android | No edge |
| Fees | |||
| Fee conditions & evidence | The general taker formula is 0.07 × multiplier × contracts × price × (1 − price), subject to schedule rounding. Maker fees use 0.0175 with a default multiplier of zero, but selected series charge maker fees. No settlement fee; funding charges depend on the payment method. Review evidence · Official fee source | Taker fees follow a formula rather than a flat percentage: "Fee = Θ × C × p × (1 - p)", with a taker theta of 0.0695. The fee peaks at $1.74 per 100 contracts at a $0.50 price, which is about 3.5% of the $50 trade value, and falls toward zero near $0.01 or $0.99. Makers currently receive a rebate with a theta of -0.0125 (up to $0.31 per 100 contracts). Takers who traded $250k to $999,999 the previous month get 10% back, $1M to $9.99M gets 25%, and $10M+ gets 50%. Combos (parlays) carry a higher taker curve that adds a 0.04 × (1-p)^4 term. The schedule has been "Effective exchange-wide from 12 AM ET, Friday September 25, 2026" (docs.polymarket.us/fees, read 28 Sep 2026). Two changes are pending. The Table Tennis taker coefficient rises to 0.10 from 30 Sep 2026. Under a CFTC 40.6(a) filing dated 22 Sep 2026, the coefficient-based maker rebate will be replaced from 6 Oct 2026 by tiered rebates for makers above $10M of monthly volume, and the filing states "The maker fee is zero." Withdrawals are described as free ("Withdraw your cash balance securely and for free"). No deposit fee is stated anywhere in the docs. Review evidence · Official fee source | Depends on the trade |
| Maker fee | See fee conditions above | See fee conditions above | No edge |
| Taker fee | See fee conditions above | See fee conditions above | No edge |
| Withdrawal fee | — | Free | No edge |
| Deposits and withdrawals | |||
| Minimum deposit | $10 | — | No edge |
| Currencies | USD | USD | No edge |
| Markets | |||
| Market categories | Politics, Sports, Crypto, Economy, Entertainment, Science, Other | Sports, Politics, Crypto, Economy, Science, Other, Entertainment | No edge |
| Public API | Yes | Yes | Tie |
| Access and regulation | |||
| Jurisdiction | United States | United States | No edge |
| Licensing | CFTC-designated contract market — Kalshi (CFTC DCM register: “Designated”, 3 November 2020) | CFTC Designated Contract Market: QCX LLC d/b/a Polymarket US (designated 9 July 2025; amended order 25 Nov 2025 permits FCM-intermediated access), CFTC Derivatives Clearing Organization: QC Clearing LLC d/b/a Polymarket Clearing (registered by order dated 16 Dec 2024) | No edge |
| KYC required | Yes | Yes | No edge |
| KYC trigger | Mandatory before trading. Kalshi requires full legal name, date of birth, a residential address (no PO boxes or commercial addresses) and a live photo of a government ID — driver’s licence or passport — and states it is “mandated to gather this specific information from all Kalshi users due to our regulatory obligations under United States (US) law”, with proof of address, employment information or source of funds possible on top (help.kalshi.com, read 31 July 2026). | At signup, before any deposit or trade: "You must complete KYC before you can deposit funds or trade." Users give their full name, date of birth and address. Some are also asked for a government ID and a selfie check, and manual review can take up to 3–5 business days. | No edge |
| Supported countries | — | — | No edge |
Regulation and track record
Kalshi appears on the CFTC’s register as designated since 3 November 2020; QCX LLC d/b/a Polymarket US since 9 July 2025. Both require identity verification before trading. Both are also in disputes with states: court orders block categories of Kalshi contracts in Nevada, Washington and Michigan, and a Nevada court has enjoined Polymarket US.
Fees
Kalshi’s general taker fee is 0.07 × price × (1 − price) per contract — about 1.75¢ at 50¢. Polymarket US uses a taker theta of 0.0695 on the same curve, peaking at $1.74 per 100 contracts at 50¢, and pays makers a small rebate. On a like-for-like trade the difference is a fraction of a cent per contract; the spread will usually matter more.
Which one suits you
Choose Kalshi if…
→Traders who want the longest-regulated US venue, or who are outside the US in a country Kalshi accepts.
Choose Polymarket US if…
→US residents who follow Polymarket’s markets and want them in a regulated dollar account.
FAQ
- Is Kalshi or Polymarket US cheaper?
- They are almost identical for takers — Kalshi 0.07 and Polymarket US 0.0695 on the same price × (1 − price) curve. Polymarket US also pays makers a rebate. Compare the spread on the market you want.
- Can I use Kalshi or Polymarket US outside the US?
- Kalshi accepts residents of many countries, excluding the 52 named in its Member Agreement. Polymarket US is for the US; outside it, the international polymarket.com is a separate product.
- Are Kalshi and Polymarket US legal in every state?
- Both are CFTC-designated, but state courts have limited both: Kalshi’s sports and other categories are blocked in Nevada, Washington and Michigan, and Polymarket US is enjoined in Nevada.