When do I file capital gains tax on stocks?

According to the National Tax Service, when you transfer shares, you must file a preliminary return and pay within 2 months from the last day of the half-year in which the transfer date falls, and if you made several transfers during a half-year, you report them together for that half-year.

Even if you have filed a preliminary return, you may need to file a final return in May of the following year if the tax amount changes, for example because progressive rates apply. Failure to file may result in penalty taxes, so be sure to check the deadlines.