An Investment Savings Account (ISK) has just a flat-rate tax which means an annual percentage tax on the value of the account instead of capital gains tax on the sale of securities. You do not need to calculate the tax on your ISK yourself, but if you want to know we will describe how to do it below. 


The simple answer is that Advinans reports a standard income to the Swedish Tax Agency every year on your behalf. The standard income then automatically shows up in your tax return and is taxed at 30%, alternatively is offset within the income category capital. Simply and securely.


The standard income is the same as the capital base multiplied by the government borrowing rate of 30 November in the previous year + 1%[1]. 


The capital base is calculated as one quarter of the total of:

  • The value of the assets in your ISK at the beginning of each quarter.
  • Deposits during the year.
  • Transfers of securities to your ISK during the year.

NB: It is common to call the ISK taxation the product of (government borrowing rate + 1%) * 30%, i.e. the flat-rate tax to be multiplied by the capital base in order to give the total tax. This tax is for the year 2021 0.375%.


A mathematical example:

Quarter 1: Value SEK 0. You have SEK 0 in your investment savings account since you only opened your account in May.

Quarter 2: Value SEK 40,000. Since you deposited SEK 40,000 in your ISK.

Quarter 3: Value SEK 45,000. You have not made any deposits but the value of your securities has increased by SEK 5,000.

Quarter 4: Value SEK 60,000. You have deposited an additional SEK 10,000 while the capital has increased by a further SEK 5,000.


This base allows us to calculate the tax for the investment savings account:

  1. Sum up your deposits and all values. There is a total of SEK 50,000 in deposits + SEK 145,000 in value, a total amount of SEK 195,000.
  2. Divide 195,000 by all quarters (195,000/4) and we get the amount SEK 48,750.
  3. Multiply the capital base SEK 48,750 by 1.25% (2020) to get the standard income ~ SEK 609.
  4. Multiply the standard income SEK 609 by the tax rate 30%. The final tax amount is SEK 182.


[1] There is a lower limit for the standard income of 1.25% of the capital base. If the government borrowing rate on 30 November the previous year is + 1% lower than 1.25%, the standard income is automatically 1.25% of the capital base.