IRS 2026 in Portugal: dates, Anexo J and filing

When is the IRS return for 2026 income due?

Under the current law, the return for income earned in 2026 is filed from 1 April to 30 June 2027. You file it online, on the Portal das Finanças.

IRS here is Portugal's personal income tax, Imposto sobre o Rendimento das Pessoas Singulares, not the US Internal Revenue Service. Its annual return is the Modelo 3. "IRS 2026" is the tax on income earned in 2026, which you declare in 2027.

The dates that matter for 2026 income:

• Household details and invoice validation. The deadlines are those the tax authority publishes for the filing season, before 1 April 2027. Most deductions depend on invoices issued with your tax number (NIF) and validated on e-Fatura.
• 1 April to 30 June 2027. The window for filing the Modelo 3 and its annexes.
• 30 June 2027. Deadline for notifying the tax authority that foreign tax eligible for a credit is still undetermined.
• 31 December 2027. The extended deadline, which applies only where that notice was given. Without it, a first return filed after 30 June is late.

Who files

Your residence in 2026 decides what your return covers. You were resident if you spent more than 183 days in Portugal in any 12-month period beginning or ending in 2026, counting the days that include an overnight stay. You were also resident if you had a home here that suggested an intention to keep it as your habitual residence.

Residence follows from these facts, not from a choice. As a resident, you declare your worldwide income, with your foreign income on Anexo J.

If you became resident during 2026, you are taxed on your worldwide income from the day your residence began. Establish that day before you declare the income of each part of the year: missing a mid-year start is a common residence error.

As a non-resident, you file only to declare income from Portugal that is not fully covered by a final withholding tax (taxa liberatória). Rent from a property here, or the gain on its sale, is the common case.

A married couple or a couple in a de facto union (união de facto), both tax resident, is taxed separately unless both opt for joint taxation in the return. The option holds for that year only, and the tax can differ, so compare both before you submit.

If you are not sure whether you were resident in 2026, or from which day, a Tax Consultation answers that question.

How to file your IRS return yourself, step by step

Seven steps take a return from your records to the assessment.

1. Sign in to the Portal das Finanças. You file with your tax number (NIF) and your password for the portal. If you have no password yet, request it on the portal well before April.
2. Gather and map your income. Collect each income statement, the withholding statements, the proof of any tax paid abroad and last year's return. Then list each income by Portuguese category and by country: employment (A), self-employment (B), capital income (E), rent (F), capital gains (G) and pensions (H).
3. Check whether IRS Automático is offered to you. It is a pre-filled return for routine cases, such as Portuguese employment income alone. Check it against your records before you accept it. With any other income, such as income from abroad, or with deductions beyond the automatic calculation, do not confirm it: file the full Modelo 3 instead. An automatic return you neither confirm nor replace by 30 June is treated as filed as it stands.
4. Complete the Modelo 3 and its annexes. Start from the pre-filled data where the portal shows it. Then add the annexes your income needs, such as Anexo A (employment), Anexo B (self-employment), Anexo J (foreign income) and Anexo L (NHR or IFICI).
5. Check the return. Cross-check the income totals, the deductions and any regime position against your records. The portal validates the return; its simulation is available only for the situations it supports.
6. Submit and keep the proof. Submit by 30 June 2027, and keep the proof of submission with your records.
7. Read the assessment. The tax authority then issues the assessment (liquidação), showing a refund or an amount to pay. Its timing depends on the tax authority's processing and on your return. If tax is due, pay it by the date the assessment gives.

These steps suit a routine return. A first return as a new resident, income from several countries, self-employment with a regime to choose, a foreign pension, or NHR or IFICI each add decisions.

How do I report foreign income on my Portuguese IRS return?

As a resident, you declare foreign income on Anexo J of your Modelo 3, by category: employment, pensions, business income, rent, investment income and gains. Each income goes in with its source country, its gross amount and the foreign tax paid on it. Record each amount in its own currency and the method you used to convert it to euros.

Tax paid abroad is credited against your Portuguese tax. The credit cannot exceed the Portuguese tax on that income. Where a treaty applies, it also cannot exceed the tax the treaty allows the other country to charge. A treaty can also decide which country taxes an income, so check the treaty article for each income before you claim the credit.

Anexo J also identifies your foreign bank and securities accounts, even those that produced no income. With IFICI, foreign income in categories A, B, E, F and G is generally exempt with progression, but pensions are not. Exempt income is still declared.

Keep the payer's statement and the proof of foreign tax with your return. The guide Foreign income in Portugal: Anexo J step by step sets out each category, treaty relief and the credit in full.

Common filing mistakes

Beyond residence and foreign income, these errors are common in returns with a foreign side:

• Regime status. Applying NHR without confirming that it still runs for 2026, or IFICI without meeting its conditions. Residence or a visa alone establishes neither.
• Letting. Leaving out income from letting a property, including short-term lets through platforms.
• Self-employment. A wrong activity code, or a misapplied coefficient under the simplified regime.
• Crypto. Short-term gains reported inaccurately, or taxable disposals left out.
• Treaty relief. Relying on a treaty without the documents that support the claim.
• Dependants. Claiming dependants or ascendants without meeting the legal conditions on living together and on their income.

Each one can change the tax due. Correcting it after you file follows the routes in the next section.

Late or wrong returns

A first return filed after the deadline is late. It can lead to a fine and interest, depending on your facts. The fine turns on how late the return is and on whether you file it of your own accord or after a notice from the tax authority.

A mistake in a return already filed is put right with a substitute return or a challenge to the assessment, each with its own procedure and deadline. Gather the return filed, the assessment and the records for that year first.

The window for 2025 income closed on 30 June 2026. A first 2025 return filed after that date is late, except where the 31 December 2026 extension for undetermined foreign tax applies. The guide IRS 2025 in Portugal: correct a return or file late covers that year.

If one or two past years were filed late, filed with errors or not filed at all, Putting past years right sets out what to correct and the consequences. We then file each year's late or substitute return. If the tax authority has already written to you with a deadline, see A letter from the tax authority.

Filing obligations outside Portugal

Your Portuguese return covers Portuguese tax only. A return due in another country follows that country's rules and dates, and your adviser there files it.

The two returns describe the same income. Prepare both from the same records: the income, the tax withheld and paid in each country, and the treaty article you rely on. Reviewing both together before either is filed carries less risk than correcting one afterwards.

If the foreign tax is settled only after 30 June, the notice described in the first section moves your Portuguese deadline to 31 December. If the other country later refunds tax or changes its assessment, the credit claimed in Portugal can need correcting.

A US citizen living in Portugal is taxed by Portugal on worldwide income and by the United States as a citizen, and so files in both countries. US returns and reports follow US rules and dates, which this guide does not cover.

Annual Tax Support includes coordination with your adviser abroad. Outside it, where the two returns must be reconciled in full, we work with your adviser abroad under Two-country returns reconciled, so that both returns are consistent.