ISK — the Flat-Rate Tax

The flat-rate tax of 30% is a fee that is deducted directly from the profit when you sell stocks or funds in an ISK. Unlike a regular stock depot, where you pay tax on the net profit (sale price - purchase price - any costs), the flat-rate tax is calculated on the account's total result for the year. This means that even if you have a stock that fell in value during the year but at the same time have another stock that did well, you may still have to pay tax on the total profit. This mechanism makes the tax structure of the ISK crucial for understanding the actual return, especially for portfolios with high revenue turnover or large profits and losses.

For an investor following a long-term strategy with few trades, the ISK is often highly advantageous. Here it is the long time periods that benefit, as the flat-rate tax of 30% becomes a smaller part of the total return over time. However, for an active trader or a portfolio with high revenue turnover, the tax can become a significant cost. For example, if you sell stocks for 100 000 kr and buy new ones for the same amount during the year, this is counted as revenue turnover that does not affect the tax. But if you realize a profit of 50 000 kr, 15 000 kr in flat-rate tax is deducted directly. To optimize this, we recommend compiling trades so that profits and losses within the same year are offset against each other, in order to minimize the total tax base.

Another practical aspect is the handling of dividends. All dividends from Swedish dividend-paying companies that are placed in an ISK are taxed with the flat-rate tax. This means that a stock with a high dividend yield becomes tax-wise less attractive in an ISK compared with a regular depot, where dividends are taxed at 30% up to 50 000 kr and thereafter 40%. For AK1A Research Lab, this is an important parameter in our valuation of companies, especially for investors who rely on continuous dividends as part of their return.