Is Polymarket legal in California? What Polymarket's two sets of terms and California law say
Is Polymarket legal in California?
Polymarket.com, run by Adventure One QSS, Inc., bars trading by anyone in the United States, California included. Polymarket US, run by QCX LLC and designated by the CFTC on 9 July 2025, publishes no list of excluded states, and no California lawsuit, cease-and-desist or Attorney General statement naming Polymarket was found as of 28 October 2026.
Piece published Reviewed by CryptoGuardz Register Desk, editorial desk
Is Polymarket legal in California? It depends which Polymarket. The international site, polymarket.com, says "Trading is blocked in the United States on polymarket.com." California is in the United States. Polymarket US, run by QCX LLC, has been a CFTC-designated exchange since 9 July 2025 and publishes no list of excluded states. No California action against either was found as of 28 October 2026.
Documents read on 28 October 2026: both sets of Polymarket terms, the Polymarket US documentation, participant agreement and rulebook, the CFTC designation order, the Ninth Circuit's tribal-gaming opinion, the California Attorney General's release of 12 June 2026, the Supreme Court docket in case 26-299 and the Governor's order of 27 March 2026. This is not legal advice.
Can you use Polymarket in California?
Not polymarket.com. Its terms, effective 11 August 2026, are with Adventure One QSS, Inc., and the trading clause opens:
USE OF THE SITE, PLATFORM OR TECHNOLOGY FEATURES FOR TRADING IS NOT PERMITTED BY PERSONS OR ENTITIES WHO RESIDE IN, ARE LOCATED IN, ARE INCORPORATED IN, HAVE A REGISTERED OFFICE IN, OR HAVE THEIR PRINCIPAL PLACE OF BUSINESS IN THE UNITED STATES OF AMERICA
Polymarket has been given the green light to go live in the USA by the @CFTC. Credit to the Commission and Staff for their impressive work. This process has been accomplished in record timing. Stay tuned
The help centre article on geographic restrictions, updated 14 August 2026, lists the United States under "Blocked Countries". The terms page adds: "This international platform is not regulated by the CFTC and operates independently." No document treats California differently from the rest of the country. The full country list is in Polymarket restricted countries.
Polymarket US is the version built for American users. Its documentation describes it as "a CFTC-regulated exchange for trading event contracts on real-world outcomes." The CFTC's amended designation order names "QCX LLC d/b/a Polymarket US" and dates the original designation to 9 July 2025. How the two products differ in practice is in How does Polymarket work?.
| Question | polymarket.com | Polymarket US |
|---|---|---|
| Operator | Adventure One QSS, Inc. | QCX LLC |
| Regulator | Not the CFTC | CFTC, designated 9 Jul 2025 |
| US trading | Blocked | Open to verified US adults |
| California named | No | No |
| Minimum age for US users | Not applicable | 18 and state age of majority |
Which states is Polymarket US available in?
Polymarket US does not say. Its documentation, its rulebook dated 30 September 2026 and version 1.4 of its participant agreement, last updated 6 August 2026, contain no list of permitted or excluded states, and none mentions California. Whether a California address clears sign-up was not verified. The agreement asks each user to warrant that they are "not domiciled, a resident of, or located in any jurisdiction in which access to, use of, or trading on" the exchange is prohibited, and adds:
PMUS may revise its policies and update the jurisdictions covered by this Section II.8, without notice to you,
Section II.1 requires a user "at least 18 years of age, having attained the age of majority in your state". The sign-up page asks for a Social Security number and says "You must complete KYC before you can deposit funds or trade."
Does Polymarket US offer sports contracts in California?
Polymarket US offers "markets on sports (NFL, NBA, NHL, MLB, MLS, college sports, tennis, golf, and more)", per its own documentation. No Polymarket US page read on 28 October 2026 limits sports contracts by state, so no document shows them switched off in California. Whether they are live for a California account was not verified.
That matters because sports betting is illegal in California. The Ninth Circuit wrote on 16 September 2026 that sports betting is legal in many states "but not in California, see Cal. Penal Code § 337a(a)(6)." The statute's own page on the Legislature's site sat behind a browser check on 28 October 2026, so its wording was not verified from the primary source.
Has California taken action against Polymarket?
No action naming Polymarket was found as of 28 October 2026. Attorney General Rob Bonta's release of 12 June 2026 joined a coalition of 37 attorneys general backing Ohio against Kalshi and called it "the seventh time California has joined nationwide multistate amicus efforts targeting Kalshi and similar prediction market companies." Polymarket is not named in it. His line:
Prediction markets cannot use federal loopholes to bypass state consumer protection, sports gaming, and gambling laws.
On 7 October 2026 California signed the brief of "Ohio, 38 Other States" in Flaherty v. KalshiEX, No. 26-299, asking the Supreme Court to hear New Jersey's case. The brief does not mention Polymarket. The question behind it, whether federal law displaces state gambling law for sports event contracts, applies to any CFTC-designated exchange listing them.
Governor Gavin Newsom issued an executive order on 27 March 2026 barring gubernatorial appointees from using confidential or non-public information from their jobs to profit from prediction markets, or to help others profit. It governs state officials, not users or platforms, and the release names no company.
The states that have sued or written to Polymarket, Nevada, Illinois, Missouri and New York, are covered in Is Polymarket legal in the US?. California is not among them as of 28 October 2026.
Does the Ninth Circuit tribal ruling apply to Polymarket?
Not directly. Blue Lake Rancheria v. Kalshi, decided 16 September 2026, was brought by two California tribes against Kalshi, KalshiEX and two Robinhood entities. Polymarket is not a party, and the opinion does not mention it. The court held the tribes are likely to show that Kalshi's sports contracts entered on tribal lands violate the Indian Gaming Regulatory Act. A tribe could bring the same argument against any exchange offering sports contracts there, but none has against Polymarket on the record read. The Kalshi side is in Is Kalshi legal in California?, and the state's gambling rules are on the California page.
Quick answers
Is Polymarket banned in California?
Polymarket.com blocks trading for everyone in the United States, under terms effective 11 August 2026. Polymarket US names no banned state. See Is Polymarket legal in the US?.
Is Polymarket US regulated?
Yes. The CFTC designated QCX LLC d/b/a Polymarket US as a contract market on 9 July 2025.
Has California sued Polymarket?
None found. No lawsuit or cease-and-desist naming Polymarket was found as of 28 October 2026. California's multistate briefs, at least 7, target Kalshi and "similar prediction market companies".
Where can I get help with gambling in California?
Call 1-800-GAMBLER (1-800-426-2537) or text SUPPORT to 53342. The National Problem Gambling Helpline is 1-800-MY-RESET (1-800-697-3738), with call, text and chat. More options are on the responsible gambling page.
Sources
- Polymarket.com Terms of Use, Adventure One QSS, Inc., effective 11 August 2026, retrieved 28 October 2026
- Polymarket.com terms page, retrieved 28 October 2026
- Polymarket Help Center, Geographic Restrictions, updated 14 August 2026, retrieved 28 October 2026
- CFTC, QCX LLC d/b/a Polymarket US, Amended Order of Designation (original designation 9 July 2025), retrieved 28 October 2026
- Polymarket US, What is Polymarket US, documentation, retrieved 28 October 2026
- Polymarket US, Create an Account, documentation, retrieved 28 October 2026
- Polymarket US, Individual Participant and Clearing Member Agreement, version 1.4, last updated 6 August 2026, retrieved 28 October 2026
- Polymarket US Rulebook, dated 30 September 2026, retrieved 28 October 2026
- Blue Lake Rancheria v. Kalshi, Inc., 9th Cir. No. 25-7504, opinion filed 16 September 2026, retrieved 28 October 2026
- California Penal Code section 337a, California Legislative Information, not verified (blocked) on 28 October 2026
- California Attorney General press release, Attorney General Bonta Joins Bipartisan Coalition Defending State Gambling Laws Against Kalshi, 12 June 2026, retrieved 28 October 2026
- Flaherty v. KalshiEX LLC, US Supreme Court No. 26-299, docket, retrieved 28 October 2026
- Brief of amici curiae Ohio, 38 other states and the District of Columbia, No. 26-299, filed 7 October 2026, retrieved 28 October 2026
- Office of Governor Gavin Newsom, Governor Newsom strengthens bans on insider betting by state officials, 27 March 2026, retrieved 28 October 2026
- California Department of Public Health, Office of Problem Gambling, helpline numbers, retrieved 28 October 2026
- National Council on Problem Gambling, National Problem Gambling Helpline, retrieved 28 October 2026
About this piece
Compiled by the CryptoGuardz register team from the sources listed above. Research and drafting are AI-assisted and reviewed by a named editor before publication. Nothing here is a recommendation to gamble. If a figure or a reading is wrong, tell us and the correction is logged in public.