Dividends and IRS in Portugal: aggregation or the flat 28%?

What tax do dividends pay?

When a company distributes profits and pays you dividends, that income is taxed under IRS as investment income (Categoria E). The default rule is simple: there is a 28% withholding at source as a final tax (Art. 71 of the Código do IRS)¹. The bank or broker withholds the 28% straight away and pays you the rest.

The key word is final: if you do nothing else, that 28% is the final tax. The dividend is not added to your other income and you do not even have to declare it. It is the simplest route, and so it is the starting point of our dividend tax calculator.

The option to aggregate

The law gives you an alternative: you can opt for aggregation (englobamento, Art. 22 CIRS). Instead of the flat 28%, you add the dividends to your other income and tax everything at the progressive IRS rates, at your marginal rate. The 28% already withheld becomes a payment on account: it is set off against the final tax and refunded at settlement if appropriate.

Why would anyone choose to pay at the marginal rate instead of 28%? Because of a rule that changes the arithmetic.

The 50% rule (Art. 40-A)

Here is the advantage of aggregation. Art. 40-A CIRS requires only 50% of dividends distributed by companies resident in Portugal or another EU/EEA state to be counted when you opt for aggregation². It is a way of softening economic double taxation: the company already paid IRC on the profit before distributing it.

Company in Portugal or the EU, with aggregation: only half the dividend is taxed.

For dividends from companies outside the EU, this reduction does not apply: the full amount counts.

Aggregation or the flat rate? A worked example

Suppose you received €1,000 of dividends from a Portuguese company and your marginal IRS rate is 35%.

• Flat rate (28%): you pay €280 of tax and keep €720.
• Aggregation: only 50% counts, so €500, taxed at 35% = €175 of tax. You keep €825.

Here aggregation saves €105. If the dividends were from a company outside the EU, the full amount would count (€1,000 × 35% = €350) and then keeping the flat 28% would pay off. Run your own numbers in the dividend tax calculator, which compares both routes.

For companies in Portugal and the EU, since only half is taxed, aggregation reduces the tax on the dividends whenever your marginal rate is below 56% (half of 56% is 28%). As the top IRS marginal rate is much lower, aggregation almost always lowers the tax on the dividends.

The catch: the rest of your income

There is an important caveat. Aggregation is not a choice for the dividends alone: it is an option that covers all income in the same category for that year. And, by adding more income to your IRS, it can raise the marginal rate applied to the rest of what you earn.

That is why, in the calculator, the marginal rate is your own field: simulate with the rate you would have after aggregating and decide looking at your full return, not just the dividends in isolation.

What about foreign dividends?

Dividends paid by foreign companies usually suffer a withholding in the country of origin (for example, 15% in the United States with a W-8BEN form). In Portugal they are still taxed at 28% (or by aggregation), but you can use the tax paid abroad as a credit for international double taxation, up to the limit of the Portuguese tax.

That withholding at source is not computed in our tool. Foreign dividends are declared in Anexo J; domestic ones you choose to aggregate go in Anexo E.

The takeaway

By default, dividends pay 28% IRS via withholding at source and are not even declared. If you opt for aggregation, you tax them at your marginal rate, but with the advantage that only 50% counts for dividends from Portugal and the EU. See which pays less tax for your case in the dividend tax calculator. As with any tax matter, when in doubt check with the tax authority or an accountant.