Missed the IRS Deadline in Portugal? Here's What to Do (2026)

The IRS filing window in Portugal runs from April 1 to June 30. If you're reading this in May or June, you still have time. If you're reading it in July or later, you've missed the deadline, and you're probably wondering how bad this is going to be.

The answer: probably not catastrophic, but not free either.

What the deadline actually means

June 30 is the submission deadline for your IRS declaration (Modelo 3) covering the previous tax year. Missing it doesn't void your obligation to file. It just means you're now filing late, and that comes with a fine.

There's no mechanism by which Portugal simply forgives a missed filing. But there's also no mechanism that makes it impossible to fix. The system is designed to accept late filings. It's unpleasant, not catastrophic.

The fine

The fine. Filing your Modelo 3 late is punishable by a coima of €150 to €3,750 (RGIT Art. 116.º n.º 1). There is no fixed €200 fine and no different scale after 31 December; within the range the amount is graded by, among other things, how long the declaration was overdue (Art. 27.º n.º 2).

Filing before AT acts gets you the reduced coima. If you ask to pay the coima before any auto de notícia, participação, denúncia or inspection, it is reduced to one eighth of the legal minimum (Art. 30.º n.º 1 a)). On €150 that is €18.75, but a reduced coima is never below €25 (Art. 26.º n.º 3), so in practice you pay €25. You keep the reduction by paying within 30 days of being notified of it and regularising in the same period (Art. 30.º n.º 3 a)). Once an inspection has started, the reduction is half the minimum, up to the audição prévia deadline (Art. 30.º n.º 1 b)).

Interest. If filing late delays the assessment of tax you owe, juros compensatórios accrue day by day from the filing deadline until you file (LGT Art. 35.º n.ºs 1, 3 and 6), at the legal interest rate (n.º 10). If you are due a refund, nothing is delayed, so no juros compensatórios.

Filing voluntarily: why it matters

There's a concept in Portuguese tax law that doesn't have an English equivalent: regularização espontânea. It means exactly what it sounds like: you identify the problem and fix it yourself, before AT formally contacts you about it.

When you file late but before AT sends a notification about the missing declaration, you're exercising this right. You're not waiting to be caught. You're correcting the situation on your own initiative.

This matters for several reasons. First, the practical one: when you act first, you control the process. You file on your own terms, with your own deductions, at a time you choose. The reduced coima and any interest are predictable costs. You pay them, and the matter closes.

Second, the escalation risk: once AT has drawn up an auto de notícia, or received a participação or denúncia, about the missing declaration, the one-eighth reduction is no longer available (RGIT Art. 30.º n.º 1 a)). The coima is then graded within the €150 to €3,750 range, taking into account, among other things, how long the declaration was overdue (RGIT Art. 27.º).

The practical takeaway: if you've missed the June 30 deadline, the best thing you can do is file now. Not when you feel ready. Not when you've gathered every document. File with what you have, correct what you can, and close the matter before AT contacts you. A reduced coima you pay voluntarily is better, in every respect, than the version that arrives with an enforcement notice attached.

What happens if you don't file at all

This is the scenario to avoid.

If you never file, AT writes to you by registered letter giving 30 days to file. It then assesses on the information it holds (CIRS Art. 76.º n.ºs 1 b) and 3): Category B income at the 0.75 coefficient (n.º 2), or your most recent known Category B net income if that is higher (n.º 1 c)). It applies the health, education, housing, general family, exigência de fatura and care-home deductions it knows about, but not the deduction for your dependants.

So AT's assessment can leave out deductions you would have claimed yourself, and filing yourself, even late, is almost always better.

The practical path if you've missed it

First: check whether you've actually missed the deadline. If it's before June 30, you haven't. The window is longer than many people assume.

If you have missed it:

1. Log into the Portal das Finanças and navigate to your IRS submission. You can still submit after the deadline.

2. File as soon as possible. Every month you wait adds more interest if you owe tax, and filing before AT acts is what keeps the reduced €25 coima available.

3. Don't ignore AT correspondence. If you ignore AT's registered letter, AT assesses on the information it holds after 30 days (CIRS Art. 76.º n.º 3).

4. Check your deductions. Review your e-fatura statement, health expenses, any other deductible costs before you file. A late filing can still include everything you were entitled to: the lateness doesn't affect the substance of the declaration, only the timing.

If your situation is complicated

Late filing gets harder when the underlying situation is also complicated: NHR or IFICI status, foreign income in Anexo J, capital gains, rental income. In those cases, the combination of a deadline miss and a complex return is worth addressing with a certified accountant (contabilista certificado). Not because the late filing is complicated, but because getting the declaration itself right takes time you may not have been giving it.

A straightforward Anexo B freelancer filing that's a month late? The reduced €25 coima and some interest. A multi-annex return with foreign income that was never filed? That's a different conversation. If you're not sure what to fill in Anexo B, the campo-by-campo field guide covers every field.

One more thing

The longer you wait, the more complex the resolution becomes, and "it works itself out" is not a plan.

The filing window is open until June 30. If you're close to the deadline and haven't started, there's still time to file correctly and avoid the fine entirely. The Descodify IRS reader can help you review your prior year's declaration and understand where your 2025 numbers need to go before you log into the portal.

If you've already missed it: file soon, file correctly, and pay the fine. It's not a pleasant afternoon, but it's manageable.

See also: IRS Filing Hub: all guides, tools, and reference material in one place