The taxpayer is entitled to deduct from investment income all expenses incurred in acquiring and maintaining such income (natural deductions).
The taxpayer has a right to deduct his interest expenses only from investment income. The interest expenses are deductible if the debt is related to the acquisition of taxable income. The interest on study loans guaranteed by the Finnish State is also deductible. The amount of these deductible interests is unlimited. If the debt is related to the acquisition or repair of the taxpayer's or his family's permanent dwelling, 85% of the interest expenses are deductible.
However, that part of the interest corresponding to the entrepreneur's private use (in partnerships and sole proprietorships) which exceeds profits derived from business activities (calculated on the basis of detailed rules), is not deductible.
Salaries, wages, pensions and other remuneration paid by a sole proprietor to a spouse or other family member under the age of fourteen are not deductible when calculating the taxable business income of a sole proprietor.
The repayment by a shareholder of a limited company of the loan he/she has received from the company is deductible, provided that the repayment takes place within five years.
The taxpayer has a right to deduct exchange losses on foreign currency debts taken for acquiring or maintaining income as natural deductions. Exchange losses relating to debts taken for acquiring income which is subject to the tax withheld at source from interest is not deductible.
The taxable capital gain is calculated by deducting the acquisition costs and sales costs from the sales price. A minimum deduction of 20 % of the sales price is applied. If the property has been acquired not less than 10 years before the sale the minimum deduction is 40 %. If the property has been received without financial consideration, the acquisition cost is the value that has been used in determining inheritance and gift tax.
A private person is allowed to deduct 50 % of an investment into young non-listed companies’ equity from his or her capital income in 2013 - 2015. The minimum eligible amount of the investment is 10,000 € and the maximum amount 150,000 €. The corresponding minimum amount of deduction is thus 5,000 € and maximum amount 75,000 €. The maximum amount of deduction per investor is 150,000 €. It is also required that the investor does not have a majority of voting power in the company before or after the investment. The deduction is returned to private person’s capital income when and if the equity stake acquired through investment is sold in the future.