Subtlety key to Japan’s gambling ad regulations: Expert
As offshore gambling websites increasingly target Japanese users with localised marketing, regulators are stepping up efforts to monitor how these platforms are being promoted online. While online gambling remains illegal in Japan, millions of people continue to access foreign sites, prompting a greater focus on advertising and affiliate content.
In recent months, Japanese authorities have investigated multiple high-profile figures over alleged online gambling activity. In June, four Saitama Seibu Lions baseball players and a club official were referred to prosecutors, followed by boy band JO1 member Shion Tsurubo, who allegedly lost about JPY 7.1 million ($49,018) on a foreign casino site. Earlier in May, Yomiuri Giants players Louis Okoye and Daiki Masuda were also referred for allegedly using offshore platforms, reportedly wagering millions of yen on games such as blackjack and baccarat. All cases involved activity prohibited under Japanese law.
Speaking at the SiGMA Asia 2025 summit in Manila, Joji Kokuryo, Managing Director of Bay City Ventures, said the country is shifting its regulatory lens toward marketing and social media channels rather than the offshore platforms themselves.
Japan’s online gambling landscape: illegal yet active
Kokuryo said the figures highlight the scale of offshore gambling activity in Japan. “Online gambling is illegal in Japan,” he stated, citing data from the National Police Agency. He said that over three million people have played using real money, with around two million still actively doing so. According to a survey by the NPA, Japan’s annual spend on these platforms is estimated at JPY 1.2 trillion ($8.2 billion).
Kokuryo pointed out that a major issue in Japan is the public’s confusion about what’s legal when it comes to gambling. A government survey revealed that 43% of respondents didn’t know that online casino gambling is illegal. He explained that this uncertainty is made worse by how legal forms of gambling, like horse racing and sports betting, are usually described as “legal betting” rather than gambling. He explained that this kind of careful language creates a grey area in the public’s understanding. As a result, many people struggle to distinguish between permitted forms of betting, such as those offered by the government, and illegal offshore gambling.
Influencer crackdown and the shift toward accountability
Kokuryo explained how Japan’s enforcement approach has changed over time. In 2023, authorities took action against a YouTuber who streamed himself gambling online with real money. He was charged and fined about JPY 10,000 ($68). The following year, Kokuryo noted, another influencer faced charges after sharing referral links to an offshore casino platform.
Kokuryo said that in recent years, public figures in Japan, including streamers, celebrities, and athletes, have faced consequences for admitting to online gambling, even if they were not formally charged. Many were made to apologise publicly, and the incidents received media attention. He referenced a high-profile case involving an affluent baseball player from the Tokyo Giants, who was charged and is now suspended from the team. There are famous celebrities who’ve lost their TV show, and they weren’t even charged yet. They just admitted to playing about eight or nine years ago.” In one instance, he noted, a person “wasn’t even charged with anything, but he lost a lot of his contracts.”
This reputational pressure, Kokuryo said, is prompting many businesses to act. “Lots of companies, especially ones involved in gaming in terms of video games, in terms of internet finance, for example, they’re undergoing compliance training on what kind of gambling is okay, what not to do,” he said.
Targeting promotion, not just play
Japan is preparing to tighten its gambling laws further. As Kokuryo explained, the country’s anti-gambling addiction law is being revised to address the promotion of offshore gambling, not just participation in it. The changes are expected to take effect from 25 September 2025.
“In the next Diet session, which is happening very soon, they plan to add two new items to the anti-gambling addiction law,” Kokuryo said. “That is the guidance or the promotion of gambling, so affiliate sites, ranking sites, and so on. And also, the promotion of free casino games that guide users to become gamblers. These two things are going to be added to the law.”
To support enforcement, Kokuryo said Japan would likely rely on existing regulatory frameworks rather than drastic new measures like website blocking. “Site blocking, very sensitive in Japan. It’s our legal right to information,” he explained. “The only thing that’s blocked in Japan at the moment is adult content that implies minors.”
Instead, the strategy is shifting toward controlling financial flows to gambling platforms. “A lot of the exchanges in Japan are sending the users emails saying, you have to be careful about what you’re transferring funds with… or we have the right to freeze that transaction,” he added, referring to recent notices issued by GMO Coin, a crypto exchange.
While changes are underway for casino-related enforcement, Kokuryo noted that sports betting may be on a different regulatory timeline. “Sports betting is probably closer than the online casino movement at the current time,” he said.
Sports betting: legal & far larger
While offshore casinos are under scrutiny, domestic sports betting is booming legally. Kokuryo cited data from the Council for Sports Ecosystem Promotion, noting that Japanese consumers place approximately JPY 5.4 trillion ($36.8 billion) in sports bets, four to five times the amount spent on online casinos.
The most popular legal options include Toto Winner, which covers football and basketball, and Japanese baseball, which sees the highest betting volumes. Although online casinos dominate the headlines, it’s clear that sports betting is Japan’s primary legal gambling driver today.
Operators must adapt: SEO, payments & compliance in focus
Kokuryo warned that even indirect promotion will come under scrutiny. Many casino SEO articles and ranking sites will fall foul of the new law. “A lot of the ads you used to see on YouTube or streaming platforms like DAZN are now disappearing,” he noted.
Japanese crypto and card payment firms are also adjusting. “A lot of the exchanges in Japan are sending the users emails saying you’re using this for gambling. We have the right to freeze that transaction.”
Authorities are increasingly relying on credit card transaction data to identify individuals involved in illegal online gambling. Kokuryo explained that the police are not necessarily tracking usernames or crypto wallets, but are instead building cases based on credit card transfers.
Enforcement is tightening, awareness must catch up
Kokuryo had a clear message for operators: anyone entering the Japanese market must prioritise subtle, localised strategies. These are no longer optional approaches; they are becoming necessary as Japan tightens its regulatory framework. With the revised law set to cover both direct and indirect promotion of offshore gambling, operators and affiliates will need to rethink conventional marketing tactics to avoid potential legal action.
As enforcement mechanisms become more precise, including monitoring of financial transactions and use of public reporting channels, the country is making it clear that while users may not always be aware of the risks, regulators are watching closely. Staying compliant will now require not just knowledge of the law, but an active effort to align with Japan’s cultural and legal sensitivities.
