2025 tax return for closely held companies – what you need to keep track of
The tax return period is approaching, and for anyone who is a shareholder in a closely held company, the K10 form is often one of the most important parts of the return. In this article, we go through some of the key points ahead of the 2025 tax return, from important dates to how the allowance (gränsbelopp) is calculated and what you should check before submitting your income tax return.
Important dates for the 2025 tax return
The Swedish Tax Agency’s online services opened on 17 March 2026. If you file digitally and simply approve the pre-filled information, any tax refund may be paid out as early as April, provided the return is approved no later than 31 March.
If you make changes, for example due to a property sale, business-related attachments or the K10 form, the return is considered amended. In that case, the refund may not be paid out in April.
The standard deadline for submitting the return is 4 May 2026. With an extension, the deadline is 1 June, and with an agent extension, the final date is 15 June.
What’s new in the tax return
For the 2025 income year, there are a few changes to be aware of:
- The interest deduction for unsecured loans has been halved.
- The temporarily increased ROT deduction applied during part of 2025 but ended on 1 January 2026.
- The threshold for state income tax is SEK 625,800.
- 2025 is the final year in which the K10 form is prepared under the old 3:12 rules. The new rules came into force on 1 January 2026.
What is the K10 form
The K10 form is used by shareholders in closely held companies to report dividends and capital gains on qualified shares. It also forms the basis for calculating the year’s allowance (gränsbelopp) and determining how much of the dividend or capital gain is taxed as capital income versus earned income.
The allowance is calculated at the beginning of each tax year. Any unused allowance can be carried forward and used in future tax years.
Calculating the allowance
The allowance can be calculated using two methods: the simplified rule or the main rule.
Under the main rule, the allowance consists of three components:
- an amount based on the acquisition cost
- a wage-based amount (based on salaries in the company and any subsidiaries)
- saved dividend allowance
Example of calculating the allowance
A shareholder owns all shares in a company. The acquisition cost is SEK 500,000 and the company has paid SEK 7 million in salaries during the year. The shareholder has received a salary of SEK 900,000.
In this case, the allowance may consist of:
- an amount based on the acquisition cost
- a wage-based amount based on the company’s salaries
The wage-based amount corresponds to 50 per cent of the company’s salary base, allocated based on ownership share. With 100 per cent ownership, the entire salary base can be used.
If the dividend during the year is below the allowance, it is taxed as capital income (at an effective tax rate of 20 per cent). Any unused allowance is carried forward.
The salary base - important requirements
To use the wage-based amount, certain conditions must be met:
- The shareholder must own shares corresponding to at least four per cent of the company’s capital.
- A salary-withdrawal requirement must be met.
- The salary base consists of 50 per cent of cash salaries in the company and any subsidiaries.
It is important to ensure which types of remuneration count as salary. Expense allowances and certain benefits are normally excluded. When calculating the 2025 allowance, the salary base is based on salaries paid in 2024.
If shares are sold during the year
When selling shares, the capital gain must be reported on the K10 form. The capital gain is calculated as the selling price minus the acquisition cost.
The portion that falls within the remaining allowance is taxed as capital income, while the excess is taxed as earned income. As with dividends, a special apportionment is applied to the amount taxed as capital income before it is transferred from the K10 form to the income tax return.
Important things to check in the tax return
There are several areas where extra care is needed:
- Classification of shares — whether shares are qualified or non-qualified affects taxation, and the assessment can be complex.
- Saved dividend allowance — errors in previous years’ calculations can affect this year’s taxation. This is especially important in cases of inheritance or gifts, as the previous owner’s saved allowance may be transferred.
- Salary base — ensure that the correct types of remuneration are included and that salaries in subsidiaries are handled correctly. Ownership changes may require apportionment.
- Pre-filled information — even if the information is pre-filled, you are responsible for its accuracy.
- Uncertain items — if something is unclear, providing an additional note may reduce the risk of a tax surcharge if the Tax Agency reaches a different conclusion.
Since the rules for closely held companies are complex, it may be valuable to review the tax return together with an adviser. A correct calculation of the allowance and salary base can have a significant impact on taxation.
Would you like to know more about how we can assist you? Read more about our tax advisory services.
