How much is the deemed acquisition cost?

20% of the sale price if held under 10 years, and 40% if held 10 years or more. The deemed cost replaces both your actual acquisition cost and your selling expenses.

When is the deemed cost better?

When your actual acquisition cost including expenses is lower than the deduction the deemed cost gives — i.e. below 20% (held under 10 years) or below 40% (held 10 years or more) of the sale price. Typically for old positions that have grown a lot in value.

Can the deemed cost create a loss?

No. The deemed cost is only used when it reduces a gain. It can never create or increase a loss — for a loss-making trade the loss is always calculated from the actual acquisition cost.

Does the deemed cost apply to futures or options?

Not to standardized derivatives. Futures and standardized options have no separate acquisition cost, so their taxation is always based on the realized result in euros.

Deemed acquisition cost (20% / 40%)

From a capital gain you can deduct either your actual acquisition cost or the statutory deemed cost — 20% or 40% of the sale price. The right choice can save hundreds of euros, and PnlTrack makes it for you.

General information, not tax advice. Verify your own situation or consult a professional.

What the deemed acquisition cost is

When you sell shares or fund units at a profit, the capital gain is calculated by deducting your acquisition cost and selling expenses from the sale price. Finnish tax law offers an alternative: instead of your actual acquisition cost, you may deduct a statutory deemed acquisition cost (hankintameno-olettama), a fixed percentage of the sale price.

The deemed cost is 20% of the sale price if you have owned the asset for under ten years, and 40% if you have held it for at least ten years. The Tax Administration automatically applies whichever option produces the lower taxable gain — but you must still report the figures correctly so the right option is chosen.

An important detail: when you use the deemed cost, it replaces both the actual acquisition cost and the selling expenses. You cannot deduct broker commissions or other costs on top of the deemed cost — it is the entire deduction.

20% or 40% — the holding period decides

The percentage is set solely by the holding period, not by the size of the gain. Ownership is counted from acquisition to disposal, i.e. from the date of one binding contract to the next. The ten-year threshold is sharp: a single day can decide whether 20% or 40% applies.

Inherited or gifted assets have special rules for the holding period, so check your own situation separately in those cases. For listed shares and ETFs the holding period is usually easy to establish from the trade dates.

When the deemed cost beats the actual cost

The logic is straightforward. The deemed cost is always worth using when your actual acquisition cost, including expenses, is lower than the deduction the deemed cost gives. The break-even points are:

Held under 10 years: the deemed cost wins if your actual costs are below 20% of the sale price.
Held 10 years or more: the deemed cost wins if your actual costs are below 40% of the sale price.

In practice the deemed cost is favourable for old positions that have grown a lot in value, and when the original purchase price is hard to document. If you bought the asset close to the current sale price, the actual cost is almost always cheaper. You can try the numbers with the capital gains calculator.

Worked example: actual cost vs 20% vs 40%

Suppose you sell a block of shares for 10,000 € and the actual acquisition cost was 1,500 € long ago.

Actual cost: 10,000 − 1,500 = 8,500 € taxable gain.
20% deemed cost (held under 10 years): deduction 2,000 €, gain 10,000 − 2,000 = 8,000 €.
40% deemed cost (held 10 years or more): deduction 4,000 €, gain 10,000 − 4,000 = 6,000 €.

If you have held the shares over ten years, the 40% deemed cost drops the taxable gain from 8,500 € to 6,000 €. At the 30% capital income rate that is 1,800 € instead of 2,550 € — a saving of 750 € on a single sale. If ownership stayed under ten years, the 20% deemed cost gives an 8,000 € gain, still slightly cheaper than the actual cost.

Key limits: it never creates a loss and never applies to derivatives

Two limits are worth remembering:

The deemed cost can never create or increase a loss. It is only used when it reduces a gain. If a trade is already at a loss, the loss is always calculated from the actual acquisition cost. Read more about deductible losses in deducting capital losses.
The deemed cost does not apply to standardized derivatives — futures or standardized options. They have no separate acquisition cost; their taxation is always based on the realized result in euros. See futures taxation for details.

Foreign (IB) shares and the euro conversion

Foreign shares traded through Interactive Brokers are often bought and sold in dollars or other currencies. Finnish taxation, however, is done in euros: both the purchase and the sale price are converted to euros at the trade-date rate (in practice the ECB reference rate). The capital gain is calculated only from the euro figures — and the deemed cost is likewise computed from the euro sale price.

This matters because a shift in the exchange rate between purchase and sale can change the outcome significantly. The same trade can be a profit in dollars but close to break-even in euros, or vice versa. Read more about the report and IB import in the Interactive Brokers tax report.

How PnlTrack picks the cheaper one for you

PnlTrack calculates both options side by side for every sale and automatically picks the one with the lower taxable gain:

Determines the holding period from the trade dates and applies the correct 20% or 40% deemed cost.
Compares the deemed cost with the actual FIFO acquisition cost including expenses.
Converts purchase and sale prices to euros at the correct trade-date ECB rates.
Never applies the deemed cost to loss-making trades or to derivatives — because it must not be used there.

You see ready figures straight for MyTax (OmaVero) without any manual Excel comparison.