Czech Republic Orders ISPs to Block Kalshi

The Czech Republic has moved to restrict access to prediction market platform Kalshi, ordering internet service providers (ISPs) to block the site after authorities classified it as an unauthorised gambling operator.

On 30 September, the Czech Ministry of Finance added Kalshi to the country’s list of unauthorised gambling operators. The decision gives ISPs a 15-day period to implement the restriction, meaning users in the Czech Republic are expected to lose access to the prediction market on 15 October.

Jan Řehola, Director of the Institute for the Regulation of Gambling and Horse Racing (IPRH), said the decision follows an approach previously applied to Polymarket.

“When Polymarket was added to the list, we said that it was an important precedent, not the end of the matter. The inclusion of Kalshi shows that this approach is now being reflected in practice. What matters should not be the name of the product, but its actual substance. If a person puts money at risk on the uncertain outcome of a real-world event, it should not be possible to circumvent the rules simply by calling the bet a contract or a financial instrument.”

The Institute considers Kalshi one of the largest platforms to have been designated under this approach. Its position is that the regulatory treatment should be based on the substance of the activity rather than whether it is described as a bet, contract or financial innovation.

Kalshi recorded approximately EUR 50.3 billion ($59.2 billion) in trading volume during September 2026. The figure represented an increase of around 48% compared with August. The platform also accounted for more than 80% of the trading volume recorded across the major prediction market platforms being monitored.

Between the beginning of 2026 and the end of September, Kalshi's cumulative trading volume reached approximately EUR 203.0 billion ($238.8 billion).

The Czech Republic has already taken similar action against Polymarket, another major prediction market platform. Czech authorities argue that prediction markets function as betting platforms despite being presented as investment instruments.

The same position has also been adopted by regulators in other European countries.