Polish capital gains tax and brokerage costs

Disclaimer: this is educational material describing mechanics, not tax advice. This lesson describes the Polish system, because the course is published in Poland; rules differ by country. Provisions and interpretations change. Status as of September 2026 — before filing, confirm the rules in official sources or with a tax adviser. This site does not provide tax advisory services.

Thesis of this lesson: the net result, not the gross

Commission and tax are not a detail — they are part of your result. Let us calculate it explicitly, instead of saying roughly eighty per cent:

About 79% of the gross profit remains — and that assumes commissions are this low. With a more expensive broker or a smaller transaction the cost share grows, while the tax share stays fixed. That is why size and strategy assessment are calculated after costs and tax, not on a pretty picture from the chart.

How the Belka tax works

Belka — 19% on capital income — applies among other things to profits from the sale of stocks and ETFs.

Two situations that must not be mixed:

• Sale of stocks and ETFs — the broker does not withhold tax, it only issues PIT-8C. You settle the entire 19% in PIT-38, by 30 April of the following year, on the sum of income from all accounts.
• Dividend — here the payer is the broker or the issuer, and it withholds the tax, so you usually receive an amount already reduced. The base is the gross amount and you do not deduct costs.

Status as of September 2026 — confirm at the source, because provisions and rates are amended from time to time.

Three things that most surprise people in practice:

1. The rate is flat. It is not progressive — 19% regardless of how much you earn at work. There is therefore no threshold above which it starts to pay off.
2. There is no tax on unrealised gains. Holding shares that have risen creates no tax. Tax arises on a sale (or on a dividend) — it is not a wealth tax.
3. You do not combine losses with income from other sources. A loss on shares will not reduce tax on your salary or on rent. It is settled only within capital income — the most common misconception and the most expensive one, if someone plans to deduct their losses against employment income. The whole frame of this income is laid out in the lesson Taxes on investments in Poland.

What may be deducted and what may not

Acquisition cost means expenses directly related to acquiring the securities — the price and the brokerage commission. The rest is sometimes a source of misunderstanding:

The last row matters when investing in foreign markets: withholding tax (WHT) collected abroad is settled through specific mechanisms, not by a simple subtraction from Polish tax. If you have significant exposure to foreign dividends, that is a topic for a conversation with an adviser, not an experiment on a tax return. The access channels to the local exchange and to foreign markets — conversion cost, session hours, and round-trip cost comparison — are laid out in the lesson Local exchange and foreign markets.

How to plan size with Belka in mind

1. You calculate the net result: gross profit minus commissions minus 19% of income.
2. Treat commissions as an entry cost within 1R.
3. For long holdings remember the difference between profit on the account and profit after tax.
4. In the journal record the net result, so that your assessment of the strategy is not overstated by tax.

Belka should not paralyse you — it should be a component of the plan. You trade in a market that is taxed; ignoring that means planning on a wrong basis.

Minimum transaction register

You do not need to keep accounts, but with several accounts or foreign investments a summary becomes necessary. Keep these columns from day one:

At the end of the year you sum the columns: income, costs, and withholding tax collected, if any occurred. The first two values must agree with the PIT-8C from your broker — if they do not, check your own register first, rather than assuming a broker error. Discrepancies most often come from an overlooked transaction or from the same transaction booked in two years.

Common practical questions

• Does a foreign ETF fall under Belka? A profit on a sale is subject to the same 19% principle. Details can differ for certain fund types and for withholding tax on dividends — confirm at the source.
• Can I deduct losses? Losses reduce profits from other transactions in a given year. The unused part is settled in later years, with an annual limit — the commonly cited rule allows half the loss per year over five years, but confirm that number in current provisions before filing. The dates of individual steps are collected in the tax calendar.
• Do I have to settle it myself? The brokerage house issues PIT-8C, but does not withhold advances on a sale, so you file PIT-38. The broker did everything is an assumption that fails with several accounts, foreign instruments, and crypto. Status as of September 2026 — confirm at the source.

When paying tax says do not trade

1. When costs and tax eat the entire edge. If your monthly execution costs are 1.5R while the strategy earns 1.2R gross, you are underwater after costs alone — tax reduces a positive result, it never deepens a loss. No improvement in psychology will change that.
2. When you plan to deduct a loss against employment income. You will not. If the plan rested on that assumption, the plan is wrong.
3. When you do not know what type of account you have. A brokerage account, a CFD account, and crypto have different settlement regimes and different obligations on your side. A comparison of the first two is in the lesson Brokerage account or CFD, and the third case is described in Crypto taxes in Poland.

Measurable exercise

Take your last month of gross profits and losses from the account. Calculate: total commissions, income, tax (19% for simplicity), and the net result as a percentage of the account. Record in the journal whether your assessment of the month would change when looking at the net figure — and by how many percentage points. That is not bookkeeping, it is the real result of your strategy.

Common questions

Do I have to settle tax on shares myself?

The brokerage house issues PIT-8C with revenue and costs, but does not withhold advances on a sale — you file PIT-38 yourself, by 30 April of the following year. With several accounts or foreign instruments that is not a formality — check the current rules on the official Ministry of Finance portal. Status as of September 2026 — confirm at the source.

Do commissions reduce the tax?

Yes — the buy commission enters the acquisition costs, and the sell commission reduces revenue. The tax effect is similar. Not every expense is a cost, however: an analytical platform subscription is not.

Can I deduct a loss on shares against my salary?

No. Losses are settled only within capital income — they will not reduce tax on employment, rent, or other sources. That is the most common and most expensive misconception in this area.

How much of the gross profit actually remains?

Without commissions, 81% remains (100% minus 19%). Commissions lower that figure. In the example from the lesson, with two commissions of 10 PLN each out of 1,000 PLN gross, 793.80 PLN remains, that is about 79%. The smaller the transaction, the larger the cost share.