Kalshi vs Polymarket: 2026 Comparison for California

On this page · 6

1. Legality in California
2. Markets and coverage
3. Pricing & fees
4. User experience
5. Who should use which
6. How we rank

Both are CFTC-regulated and available to Californians (minimum age 18 on both; we recommend 21+). Kalshi is #1 on our scorecard and the breadth leader: politics, sports, economics, weather and macro, on any device including desktop, with a $25 bonus after $25 in trades. Polymarket US is #2 on our scorecard, with its headline sports, politics and culture markets in one US app, and new traders can claim a $25 trading bonus with code CAPREDICTS. Open Kalshi first if you want the widest market list; open Polymarket US first if you mainly trade its headline markets.

Kalshi first for breadth; Polymarket US for headline markets.

• #1, broadest CFTC market coverage. Trade $25 and get $25 with code CAPREDICTS. Best for politics and the widest US event-contract mix.
• #2 overall. Headline sports, politics and culture markets in one US app.

Legality in California

Both are CFTC-regulated and available to eligible California residents (dispute pending). Kalshi operates as a Designated Contract Market (DCM) directly. Polymarket is offering US event contracts through its acquired CFTC-licensed exchange. Kalshi has the longer regulatory track record; Polymarket was fined by the CFTC in 2022 before returning through acquisition.

Markets and coverage

Kalshi has the broadest US coverage today: politics, sports, economics, culture, weather, crypto. Polymarket's US app now carries its headline political, cultural and sports markets. On the first Sunday of the 2026 NFL season, Kalshi handled about three quarters of tracked NFL trading volume, according to Aldrin Research data reported by Covers on September 14, 2026. Kalshi still wins on the long tail: weather, niche macro prints and small political races that Polymarket does not list.

Pricing & fees

Both charge modest per-contract fees. Kalshi's fees are transparently disclosed at order entry. Since October 2026, Polymarket US charges a price-based taker fee (highest near 50¢, about $1.74 per 100 contracts). Orders that rest on the book pay no fee; rebates on them are limited to very high-volume traders from October 19, 2026. On liquid markets, real costs are comparable.

User experience

Kalshi's interface is finance-forward: clean, fast, category-organized, feels like a trading app. Polymarket's product has historically been more visual and social: prominent charts, news context, community commentary. Different audiences: Kalshi for execution focus, Polymarket for context-rich trading.

Who should use which

Use Kalshi if: you're opening your first California account, you want broad market coverage today, you value the longest CFTC track record. Use Polymarket if: you specifically want exposure to its global cultural and political markets as US coverage expands. Many serious traders will eventually hold both.

Want a second opinion? Read this outcome-driven head-to-head (opens in a new tab).

How we rank

The ranking comes from the scorecard on our methodology page. Each platform is scored on five things:

• Regulation and California availability (25%): who regulates the platform and whether California residents can open an account.
• Fees and order fills (25%): trading, deposit and withdrawal fees, and how our test orders were filled.
• Market range and liquidity (20%): how many markets are live and how much trading there is on the main contracts.
• Deposits and withdrawals (15%): which payment methods work and how long the money takes to arrive.
• App quality and support (15%): app stability, the website, and how support answered a test request.

The sign-up offer is shown for each platform but is not part of the score.

Tested by Catie Di Stefano, who opens an account, deposits our own money, places trades and withdraws. The full process is on our methodology page.

We earn a commission when you open an account through the links on this page. That is how this site is funded. See our affiliate disclosure.

When each platform was last checked

• Kalshi: September 17, 2026
• Polymarket: September 25, 2026

Check the facts yourself

• CFTC list of designated contract markets (opens in a new tab)

  The federal regulator's own list of exchanges allowed to offer event contracts.

• California Attorney General: gambling in California (opens in a new tab)

  The state's own summary of what counts as legal gambling in California.

• Commodity Exchange Act (7 U.S.C. § 1 et seq.) (opens in a new tab)

  The federal law these exchanges operate under. Courts are still deciding how far it overrides state gambling law.

Fees, state lists and offer terms come from each operator's own fee schedule and terms, which we read during testing.

Frequently asked questions

Is Kalshi or Polymarket legal in California?

Kalshi is a CFTC-regulated exchange that accepts California residents (Kalshi's minimum age is 18; we recommend 21+). Polymarket US is a CFTC-regulated exchange that accepts California residents (Polymarket's minimum age is 18; we recommend 21+).

Which has lower fees, Kalshi or Polymarket?

Both platforms charge modest fees compared to sportsbook vig. Kalshi's fees are transparently disclosed at order entry. Since October 2026, Polymarket US charges a price-based taker fee (highest near 50¢, about $1.74 per 100 contracts). Orders that rest on the book pay no fee; rebates on them are limited to very high-volume traders from October 19, 2026. Exact costs depend on market and trade size.

Which platform has more liquidity?

Globally, Polymarket has reported larger volumes due to years of offshore activity. In the US, it depends on the market: on the first Sunday of the 2026 NFL season, Kalshi handled about three quarters of tracked NFL trading volume (Aldrin Research data reported by Covers, September 14, 2026). Kalshi also lists many smaller markets, such as weather, niche economic data and small political races, that Polymarket US does not.

Can I use both Kalshi and Polymarket?

Yes. Many active traders hold accounts on both. The platforms have different strengths. Kalshi for breadth and regulatory track record, Polymarket for cultural and political depth.

Is Polymarket fully available in the US yet?

Yes. Polymarket's CFTC-regulated US app is live and carries sports, politics and culture markets.

Which platform should I use for sports?

For most sports markets today, Kalshi's coverage is broader. If you only trade sports, ProphetX, a sports-first CFTC-licensed exchange, is a strong alternative to both.

Which platform should I use for politics?

Kalshi lists a wide range of political markets in the regulated US market today, including small races. Polymarket historically dominated election markets globally but its US political coverage is still expanding.

Does Kalshi or Polymarket offer better bonuses for new users?

Promotional offers change frequently. Check each platform directly for current new-user bonuses. Our platform reviews are updated with the latest offers when they materially change.