Polymarket in Japan: Restrictions and Legal Risks

On this page

Start with the international and US product distinction
What the Japan restriction actually says
Eight separate questions behind “can I use it?”
How to read the police warning and the FSA’s answer
A Japanese exchange’s transfer policy can also matter
Common questions

Polymarket is restricted in Japan. Its Help Center lists Japan as blocked, while its developer documentation describes the ordinary website interface as close-only for existing positions. Neither description supports starting unrestricted new trades from Japan.

The legal question is separate. Japan’s gambling rules, the Financial Services Agency’s comments on prediction markets and a crypto exchange’s transfer policy each address a different issue. A Japanese-language page or news about expansion plans does not establish permission to trade.

Start with the international and US product distinction

This guide concerns Polymarket.com, the international platform. Polymarket US is a separate product with separate accounts and support. The official product comparison distinguishes them. US regulation, identity checks or payment arrangements cannot be treated as the conditions for using the international platform from Japan.

What the Japan restriction actually says

The Help Center’s geographic restrictions include Japan among blocked countries. The developer documentation places Japan in the close-only group for the ordinary website interface. Close-only describes orders to close existing positions, rather than open new ones.

The documents describe different scopes, so they do not provide a consistent assurance about access, processing existing positions or withdrawing funds. Close-only does not guarantee that your order will execute, or establish that closing a position is permitted under Japanese law.

Eight separate questions behind “can I use it?”

Polymarket Global: what is established for Japan and what remains unresolved
Stage	What you need to distinguish
Website access	Japan is subject to published restrictions. A page opening does not prove eligibility; this guide includes no Japanese network test.
Terms and geography	Japan is restricted. Public help pages do not establish all contractual conditions; the full operative Global terms were not available for this guide.
Signup	Individual eligibility to register and use an account from Japan has not been established.
Identity checks (KYC)	Acceptance of Japanese documents and any additional checks remain unconfirmed.
Funding	A way to transfer assets does not establish eligibility or legal permission to fund an account from Japan.
Trading	The ordinary website interface is not described as open for new positions. Existing-position actions also need account-specific and legal checks.
Withdrawal	Closing a position, redeeming after market resolution and receiving funds externally are different steps. No Japan-specific guarantee is established.
Japanese law	General gambling rules matter, alongside the facts of the particular contract and conduct.

How to read the police warning and the FSA’s answer

Japan’s National Police Agency explains that gambling from within Japan through an online casino is a crime even if the casino operates legally overseas. An overseas licence or the service’s name does not establish permission for conduct in Japan. The warning itself does not classify every Polymarket contract.

Articles 185 and 186 of the Penal Code address gambling and habitual gambling, among other conduct. Article 185 has an exception concerning things used for temporary amusement. That exception should not be turned into a general allowance for small cash or crypto bets.

At the House of Councillors Committee on Financial Affairs on 21 April 2026, an FSA official said that betting-type prediction markets of the kind raised in the question were not then subject to a regulatory law administered by the FSA. The official also called for an extremely cautious response in light of concerns about gambling. The answer and follow-up on gambling offences and other issues do not grant approval. The absence of an FSA-administered law is not the absence of Japanese law.

A Japanese exchange’s transfer policy can also matter

In its 15 June 2026 warning, bitbank names Polymarket and says it may suspend accounts when it identifies transfers to or from prediction-market services, or services suspected of being related to them. It says suspension prevents login, crypto deposits and withdrawals, yen withdrawals and trading.

This is bitbank’s own policy, not a law shared by every exchange. It nevertheless shows why a platform’s general withdrawal feature does not establish the conditions for receiving money through a domestic service.

For general background, see our prediction-market trading guide, fee guide and Polymarket and Kalshi comparison. These explain mechanics and differences; they do not establish local trading permission.

Common questions

Is Polymarket legal in Japan?

Japan has general gambling prohibitions, and Polymarket has geographic restrictions. The sources here do not establish lawful, unrestricted trading from Japan, nor a single final legal determination covering every contract and action. For a specific legal decision, take the contract terms and proposed conduct to a qualified Japanese legal professional.

Does a Japanese page or a market-entry announcement mean I can trade?

No. Language support and expansion plans do not establish registration, funding or trading permission. Check the restrictions for the relevant product rather than treating visibility or corporate plans as approval.

Can I definitely withdraw funds from existing positions, or simply use another platform?

No guarantee follows from either option. Existing-position orders, market resolution, redemption, identity checks and the receiving service’s conditions are separate. Ask official support about your account. Other platforms, including HypaForecast, require their own terms and Japanese-law assessment; Polymarket’s restrictions do not establish their lawful availability.

This guide is published by HypaForecast and is independent of Polymarket. Links to HypaForecast do not establish that you are eligible to use its products or that trading is legally permitted where you are. Check the service’s conditions and applicable local rules separately.

Explore HypaForecast markets

Browse the market list, or inspect the question and current round details for the 5-minute and 15-minute BTC markets.

View markets View 5-minute BTC View 15-minute BTC

Sources and scope

HypaForecast reviewed official Polymarket documentation, Japanese legislation, National Police Agency guidance, parliamentary answers and bitbank’s policy. Sources were checked on 15 October 2026. No Japanese network, signup, identity, funding, trading or withdrawal test was performed. Individual legal and account outcomes remain unresolved.