How to report capital gains on shares and ETFs (Portugal IRS)

Where do you report capital gains on shares and ETFs?

When you sell shares, ETFs or funds for more than you paid, that gain (the capital gain) is Categoria G income for IRS and is reported in Anexo G of the Modelo 3 return¹. For each sale, Anexo G asks for the acquisition date and value, the disposal date and value, and the costs incurred, such as broker commissions and stamp duty.

Tax is not charged on the sale value, only on the gain. If you first want to understand what a capital gain is and how the profit is worked out, see the article on what capital gains are. This guide covers the next step: how and where to report that gain on your IRS return.

Anexo G or Anexo G1: what is the difference?

There are two annexes with similar names, and mixing them up is a common mistake:

• Anexo G: taxable capital gains. This is where almost all sales of shares, ETFs and funds go.
• Anexo G1: non-taxable capital gains. The best-known case is shares acquired before 1 January 1989, which are exempt under the transitional regime and are still reported, in G1.

In other words: G is where you pay, G1 is where you declare a gain that does not pay. For the vast majority of private investors today, the right annex is Anexo G.

What to enter in Anexo G

Each line of Anexo G corresponds to a sale (a disposal). To fill it in you need:

• The year and month of acquisition and the acquisition value (what you paid for the securities, including the buy commission).
• The year and month of disposal and the disposal value (what you received on the sale).
• The costs and charges: the buy and sell commissions and the broker's stamp duty.
• The country of the issuing entity and the identification of the securities.

When you bought the same securities on different dates, the FIFO rule applies (first in, first out): the earliest-bought are treated as sold first. You can estimate the result of each sale in the capital gains calculator before copying the values into the annex.

28% or aggregation: what to choose?

The gain on shares, ETFs and funds is, by default, subject to a 28% autonomous rate (Art. 72 of the IRS Code)². It is a flat rate, separate from your other income, and it is the normal scenario for most people.

Alternatively, you can tick the aggregation option (englobamento) in Anexo G: the gain is added to your other income and taxed at the progressive IRS rates. That only pays off at lower incomes, where your marginal rate falls below 28%. In the capital gains calculator, the rate is editable for exactly this case: leave it at 28% for the normal situation, or replace it with your marginal rate to compare.

Mandatory aggregation: the 365-day rule

There is one case where aggregation stops being a choice. If you sold assets held for under 365 days and your taxable income, including that gain, reaches the top bracket of IRS, aggregating those gains is mandatory (Art. 72 of the IRS Code)². It is a rule that stops the flat 28% rate from applying to short-term gains at the highest incomes. For anyone outside the top bracket, or holding the securities for more than a year, the 28% rate remains the rule.

I sold at a loss: carrying losses forward

If a sale lost money, you have a capital loss. Losses pay no tax and reduce gains of the same type in the same year: what counts is the balance (gains minus losses).

If the year's balance is negative, that loss can be carried forward for five years (Art. 55 of the IRS Code)³, but only if you opt for aggregation in the year of the loss and in the years you use it. Without aggregation, the year's loss does not carry over. It is an easy point to miss and one that can save future tax.

Shares and ETFs on foreign brokers: Anexo J

Many investors use foreign brokers (Trade Republic, Degiro, Interactive Brokers and others). Gains and income earned outside Portugal do not go in Anexo G, but in Anexo J (income earned abroad). The calculation logic is the same (gain at 28% or aggregation), what changes is the annex where it is reported.

From 2026, foreign platforms start automatically reporting Portuguese residents' operations to the tax authority (DAC8 rules). It is a transparency change, not a change to the rates, but it underlines how important it is to report everything correctly.

A worked example

You bought €4,000 of an ETF and sold it for €6,000, with €40 of buy and sell commissions. The gain is €1,960 (6,000 − 4,000 − 40).

• At the 28% autonomous rate, you pay €548.80 of IRS (28% of €1,960) and keep €1,411.20.
• If in the same year you had a €460 loss on another sale, the taxable balance would fall to €1,500, and the tax at 28% would be €420.

In both cases you report the sales in Anexo G. You can check your numbers in the capital gains calculator.

The takeaway

Capital gains on shares, ETFs and funds are reported in Anexo G (or Anexo J, if the broker is foreign), pay 28% by default, and aggregation only pays off if your marginal rate is lower. Losses reduce the year's gains and, with aggregation, carry forward for five years. Run your numbers in the capital gains calculator and, if in doubt about the return, check with the tax authority or an accountant.