South Korea's media regulator has approved measures to block nationwide access to Polymarket, ruling that the prediction-market platform provides an illegal gambling environment for domestic users.

The Korea Communications Standards Commission (KCSC), the body that rules on whether online content is deemed illegal information in South Korea and subject to blocking by domestic internet providers, approved the blocking measures on August 18. In its decision, the commission cited Polymarket's markets on politics, elections, sports and other events, as well as its winner-take-all payout structure, saying the platform's design can encourage speculative gambling under South Korean law.

The gambling designation carries particular weight in South Korea, where most forms of gambling are illegal for citizens and permitted only through narrow exceptions such as the state lottery and a small number of licensed betting operations.

Regulator Rejects Polymarket's Defense

Polymarket had argued that its non-custodial, peer-to-peer structure and its use of smart contracts place it outside traditional gambling rules. The company said it does not directly hold or manage users' funds and does not operate conventional betting accounts.

The KCSC rejected that argument, stating that South Korean law cannot be avoided based on a platform's technical structure. The regulator pointed to Polymarket's role in creating markets, setting trading rules, and facilitating cryptocurrency deposits, withdrawals and settlements. It concluded that the platform's technical architecture did not exempt it from South Korean law and that blocking access was unavoidable.

Decision Follows Election-Betting Probe

The KCSC investigation began in late May following a complaint. Separately, Gangwon provincial police opened a criminal investigation in early June into local users who allegedly placed bets on regional elections.

Polymarket was given an opportunity to respond to the commission on July 6 before the final decision was reached.

The cases highlight the growing scrutiny of prediction markets in South Korea, where betting on elections and other events can trigger criminal and regulatory restrictions. With this move, South Korea joins France, Germany, Italy, Singapore, Indonesia, Spain, Brazil, India and Argentina among the jurisdictions that have restricted or blocked Polymarket access over similar concerns, adding to a growing pattern of regulators rejecting decentralization-based defenses against gambling and securities laws.

South Korea's won was the world's second-most-used currency for cryptocurrency purchases in 2025, according to Chainalysis, underscoring the country's strong crypto adoption and its potential importance as a market for prediction-market platforms. Polymarket itself has recorded $58.49 billion in trading volume since the start of 2026, according to DeFiRate.

The decision could also influence how other Asian regulators, including those in Japan and Australia, approach prediction markets.