Portuguese taxes do not arrive on one date. They spread across the year, often with pre-filing obligations that many foreign residents miss entirely, and only discover when their IRS return is less favourable than expected.
This page covers every major tax deadline in 2026 for a foreign tax resident in Portugal: what the deadline requires, whether it applies to you, and what happens if you miss it. Use it as a reference throughout the year.
Quick Answer: The main IRS filing window runs from 1 April to 30 June 2026. But three earlier deadlines matter just as much: long-duration rental contract communication by 16 February, and both e-Fatura invoice validation and household composition update by 2 March. IMI payments normally fall in May, August, and November depending on the amount: one instalment up to €100, two instalments over €100 and up to €500, and three instalments above €500. IUC vehicle tax is due in your vehicle’s registration month. All tax administration happens through the Portal das Finanças at portaldasfinancas.gov.pt.
How to Use This Calendar
Not every deadline applies to every person. Use the table below as a quick reference, then read the sections that match your situation. Deadlines marked universal apply to all Portuguese tax residents who earned income in Portugal in 2025. Those marked conditional apply depending on your income type, property ownership, or household circumstances.
The calendar covers 2026 obligations. Some of the earlier deadlines (February and March) have already passed by the time you are reading this. Those sections still explain what they covered and what remains possible.
2026 Tax Deadline Table for Foreign Residents
| Date | What it covers | What you must do | Who it applies to | If you miss it |
|---|---|---|---|---|
| 16 Feb 2026 | Long-duration rental contracts | Communicate contract duration or cessation to AT | Landlords with residential leases of 2+ years | May lose associated tax benefit |
| 2 Mar 2026 | e-Fatura invoice validation | Review, register, and classify 2025 invoices in e-Fatura | All tax residents with NIF invoices | Deductions may be lower or misclassified |
| 2 Mar 2026 | Household composition | Confirm agregado familiar as of 31 Dec 2025 | Anyone with household changes or joint/dependent filing | AT uses prior-year data by default |
| 16–31 Mar 2026 | Deduction review and complaints | Check AT’s provisional deduction totals and complain about eligible discrepancies | All tax residents claiming deductions | Deductions may be lower than expected when filing opens |
| 31 Mar 2026 | IRS/IVA consignação | Choose whether to allocate 1% of IRS and/or VAT deduction to an eligible organisation | Optional for tax residents | Option is unavailable after the deadline |
| 1 Apr 2026 | IRS filing opens | File Modelo 3 or check IRS Automático if eligible | All tax residents required to file | Opening date; no need to file on day one |
| May 2026 | IMI first instalment | Pay IMI using the reference in Portal das Finanças | Property owners | Interest and enforcement risk |
| 30 Jun 2026 | IRS filing closes | Submit Modelo 3, confirm IRS Automático, or request an extension before the deadline if eligible | All tax residents required to file | Coima risk under RGIT Article 116 |
| 31 Jul 2026 | IRS assessment target | AT should issue assessments for timely-filed returns by this point | Taxpayers who filed on time | Check Portal das Finanças if nothing appears by early August |
| 31 Aug 2026 | IRS refund or payment deadline | Receive refund or pay tax owed using the reference in the nota de liquidação | Timely filed IRS returns | Interest and enforcement risk after the deadline |
| Jul 2026 | Recibos verdes quarterly declaration | Submit declaração trimestral (Q2) | Self-employed workers | Fine and contribution correction risk |
| Aug 2026 | IMI second instalment | Pay second IMI instalment if your bill is above €500 | Property owners with bills split into three instalments | Interest and enforcement risk |
| Sep 2026 | AIMI payment | Pay AIMI if threshold is exceeded | Property owners above AIMI threshold | Enforcement risk |
| Oct 2026 | Recibos verdes quarterly declaration | Submit declaração trimestral (Q3) | Self-employed workers | Fine and contribution correction risk |
| Nov 2026 | IMI later instalments | Pay second instalment for €100–€500 bills or third instalment for bills above €500 | Property owners with bills split across instalments | Interest and enforcement risk |
| Vehicle reg. month | IUC vehicle tax | Pay via Portal das Finanças | Vehicle owners | Fine and possible enforcement action |
| By 20th of each month | Segurança Social contributions | Pay monthly contribution | Self-employed workers and other contributors | Interest and contribution debt |
The Pre-IRS Deadlines People Miss Before April
Most attention goes to the June IRS deadline. The deadlines that actually shape the quality of your IRS return came earlier.
16 February 2026 — Long-duration rental contracts
If you own property and have a residential lease of two years or more, you were required to communicate the contract duration (or any cessation) to AT by 16 February. The legal deadline is 15 February; in 2026, this fell on a Sunday, so AT transferred it to 16 February. This obligation affects landlords, not tenants.
2 March 2026 — e-Fatura invoice validation
This was the deadline to log into faturas.portaldasfinancas.gov.pt and check, correct, and classify your 2025 invoices. The legal deadline is end of February; in 2026, 28 February was a Saturday, so AT moved it to Monday, 2 March.
Invoices in “Complementar Informação Faturas” status needed manual input. Misclassified invoices could be reassigned. Missing invoices could be added manually. After this date, fine-grained control over invoice categories is limited. The full breakdown of what e-Fatura does and which categories apply is in the e-Fatura Portugal guide.
2 March 2026 — Household composition
Same deadline, different obligation. You must confirm your agregado familiar (household composition) as it stood on 31 December 2025. This includes changes from marriage, divorce, births, deaths, or custody arrangements. If you made no update, AT applies the information from your last filed return by default.
This matters for foreigners because household composition affects whether you can file jointly, how dependent deductions are calculated, and the applicable tax coefficients.
IRS Filing Season: 1 April to 30 June 2026
The filing window for 2025 income runs from 1 April to 30 June 2026. All Portuguese tax residents who are required to file must submit by 30 June.
Who must file: Generally, all Portuguese tax residents who earned income in 2025. This includes employment income, self-employment income (recibos verdes), rental income, investment income where aggregation applies, and — critically for foreigners — foreign income from any source. Tax residency applies if you spent more than 183 days in Portugal in 2025, or if you maintained your habitual residence here on 31 December 2025.
Modelo 3 vs IRS Automático: IRS Automático is a pre-filled return AT prepares for taxpayers with simple income profiles — typically only Category A employment or Category H pension income from a single Portuguese source. It is not appropriate for most foreigners. If you have foreign income, NHR or IFICI status, capital gains, rental income, or any income not already captured in AT’s systems, file Modelo 3.
IRS Automático is not an opt-out you manage in March. It appears during the filing window (April to June) as a draft return in your portal. If eligible, you review it and confirm. If something is wrong or incomplete, you override it and file Modelo 3 manually. Letting the deadline pass without filing, either manually or via the automatic route, is treated as non-filing.
Filing Modelo 3: Log into portaldasfinancas.gov.pt and navigate to Cidadãos → Entregar → IRS → Declaração de IRS. Select tax year 2025. Most foreign residents working in Portugal need at minimum Annex A (employment income from Portuguese sources). Those with foreign income add Annex J. Self-employed workers file Annex B. Annex H covers deductions not captured automatically by e-Fatura.
The IRS Portugal guide for foreign residents covers each annex and the filing process in detail.
After You File: Refunds, Nota de Liquidação, and Payment Deadlines
Filing is not the end of the process. What comes next is the assessment.
AT processes returns after filing. For returns filed on time, the official IRS timetable points to assessment/refund/payment being settled by the end of August, and the normal legal payment deadline is 31 August when assessment is issued on time. In practice, you should check Portal das Finanças from July onward for the nota de liquidação (tax assessment notice). This document shows:
- Total taxable income AT calculated
- Tax due based on applicable rates and deductions
- Withholding already paid during the year
- The balance: either a refund or an additional amount owed
Check your nota de liquidação in the Portal das Finanças. Do not wait for a paper letter; it may arrive late or to an old address. If the nota de liquidação shows tax owed, pay using the exact reference in the document. For timely-filed returns, treat 31 August 2026 as the key payment deadline. Missing it can trigger interest and later enforcement. Do not make a generic transfer without the correct payment reference.
Refunds are paid to the IBAN registered in your Portal das Finanças account. Make sure it is correct before you file. If the IBAN is wrong or missing, your refund will be delayed or returned.
Deadlines That Depend on Your Situation
IMI (Imposto Municipal sobre Imóveis) — property owners only
IMI is the annual property tax charged by the municipality on the registered value (valor patrimonial tributário) of real estate. AT sends a payment reference to your portal. Payment timing depends on the total amount:
- Under €100: single payment in April
- €100 to €500: two instalments — April and November
- Over €500: three instalments — April, July, and November
AIMI (Adicional IMI) is a surcharge that applies when total property values across Portugal exceed €600,000 for an individual. Payment is due in September.
IUC (Imposto Único de Circulação) — vehicle owners only
IUC is not tied to a universal date. It falls due in the calendar month matching your vehicle’s first registration. If the car was registered in October, IUC is due each October. Pay via the Portal das Finanças using the vehicle registration plate. Owning the car in January does not mean paying in January; the registration month is what matters.
Recibos verdes workers — quarterly obligations
If you file recibos verdes as a self-employed worker, you have quarterly declaração trimestral obligations due in January, April, July, and October. These declarations support your Segurança Social contribution calculation. The contribution itself is generally due by the 20th of the following month — for example, January contributions are due by 20 February.
The Segurança Social Direta guide covers how contributions are calculated for independent workers.
US citizens and taxpayers with US filing obligations
Portugal’s IRS system and US tax obligations run in parallel. The US filing deadline of 15 April (with extensions) does not affect the Portuguese 30 June deadline. Both must be met independently. If you are a US citizen living in Portugal, consider an accountant familiar with both systems.
If you arrived in Portugal mid-year
Do not assume your tax year starts on the day you arrived. Portuguese tax residency can be triggered by the 183-day rule or by having a home in conditions that suggest habitual residence. Some cases may require split-year analysis. If you moved during 2025, confirm your residency start date before deciding what income belongs in your 2026 IRS filing.
IMI months and checking your payment reference
AT’s IMI guidance states that IMI is normally paid in May for bills up to €100, May and November for bills over €100 and up to €500, and May, August and November for bills over €500. Always check the payment reference in Portal das Finanças because the actual note of collection is what you must pay against.
IBAN before filing
Refunds go to the IBAN registered with AT. Check it before submitting IRS, especially if you changed banks or use a non-Portuguese account. A wrong or missing IBAN can turn a normal refund into a delay.
Late Filing, Coimas, and What to Do If You Miss a Deadline
| Problem | Risk | What to do |
|---|---|---|
| IRS filed after 30 June | Coima under RGIT Article 116 (general range €150–€3,750 for late or failure to file); interest on tax owed | File as soon as possible; check AT notifications |
| Tax owed but unpaid | Interest accrues; AT may initiate collection | Pay using the reference in nota de liquidação |
| e-Fatura deadline missed | Deductions may be lower or misclassified | Add missing items manually in Anexo H during filing |
| Household composition not updated | AT uses prior-year data | Effects show in IRS assessment; contact AT if figures are significantly wrong |
| IRS Automático confirmed with errors | May count as incorrect filing | Submit a replacement declaration and contact AT if blocked |
| IUC not paid | Fine and possible enforcement | Pay immediately through Portal das Finanças using plate number |
RGIT Article 116 sets the general coima range for late or failure to submit declarations as €150 to €3,750. The exact amount depends on the specific situation and whether AT issued a demand before you filed voluntarily. Filing late but before receiving a demand generally reduces the penalty.
Do not ignore AT notices or letters. Demand notices have their own response deadlines, and missing those adds complexity.
Common Mistakes
Mistake: Filing on 1 April before data stabilises
You do not need to file on the first day. For many taxpayers, mid-April is a safer practical target because pre-filled data and e-Fatura deduction figures are more likely to be stable. File early enough to avoid deadline pressure, but not so early that you skip basic checks.
Mistake: Thinking the IRS deadline is April instead of June
The filing window opens on 1 April. It closes on 30 June. Some people see “April” and assume that is the deadline. It is not. But April is also not meaningless; filing early gives you more time to correct errors before the window closes.
Mistake: Missing the pre-IRS March deadlines and only checking deductions after filing opens
The 2 March deadlines for e-Fatura and household composition directly affect the deductions and data in your Modelo 3. If those steps were skipped, your pre-filled return may have lower deductions than expected. The time to fix this was before April, not during it.
Mistake: Treating IRS Automático as safe when foreign income or special regimes apply
IRS Automático does not prompt for Annex J, NHR/IFICI elections, or capital gains from foreign sources. Accepting a pre-filled return that omits these items is a filing error, not a safe shortcut.
Mistake: Not checking the nota de liquidação after filing
Filing is not the last step. AT’s assessment may differ from your self-calculated expectation. If tax is owed, you have a deadline after the assessment to pay. Ignoring the nota de liquidação means missing that deadline.
Mistake: Forgetting IUC because it depends on vehicle registration month
There is no single IUC date. It falls in whatever month matches your vehicle’s first registration. New residents who registered a vehicle in, say, September may miss the October due date because they were not yet tracking Portuguese tax obligations at that point.
Mistake: Paying tax without using the correct payment reference
AT generates a specific payment reference for each tax demand. If you transfer money without this reference, the payment may not be attributed correctly and AT may still consider the amount outstanding. Always use the reference number from your Portal das Finanças.
Mistake: Assuming foreign income requires no Portuguese filing
Tax residents in Portugal declare worldwide income. “I only earn abroad” is not an exemption from filing. You file Modelo 3 with Annex J, declare the foreign income, and apply any applicable double taxation relief. Skipping the filing entirely exposes you to penalties.
Mistake: Forgetting Segurança Social quarterly declarations as a recibos verdes worker
Self-employed workers on recibos verdes have a separate set of obligations through Segurança Social Direta. Forgetting the quarterly declaration is a common mistake for newly independent workers who focus only on the IRS deadline.
If you are under 35, pair this deadline calendar with the IRS Jovem Portugal 2026 guide to check whether the youth exemption should be claimed in your return.
Frequently Asked Questions
What is the IRS filing deadline in Portugal for 2026?
The IRS filing window for 2025 income runs from 1 April to 30 June 2026. All Portuguese tax residents must file by 30 June. Missing this deadline can result in a coima (fine) under RGIT Article 116, even if no tax is owed.
What is the e-Fatura deadline in Portugal for IRS 2026?
For 2025 income, the e-Fatura invoice validation deadline was 2 March 2026. The legal end-of-February deadline fell on a Saturday, so AT transferred it to the next working day. After this date, your ability to reclassify invoices by category is limited.
What is the household composition deadline and why does it matter?
The deadline to update your agregado familiar (household composition) in Portal das Finanças was also 2 March 2026. This affects how AT calculates your IRS — including dependent-related deductions, joint filing rules, and shared custody arrangements. If you do not update it, AT uses the information from your previous year’s return.
Do I need to file Portuguese IRS if I only have foreign income?
Yes, in most cases. Portuguese tax residents must declare worldwide income. If you are tax resident in Portugal and earned foreign income in 2025, you generally need to file Modelo 3 and complete Annex J. The fact that you earned nothing in Portugal does not exempt you from filing. Consult a tax adviser if your situation is complex.
What happens if I miss the IRS deadline in Portugal?
Filing after 30 June exposes you to a coima (administrative fine) under RGIT Article 116. The general range for late or failure to submit declarations is €150 to €3,750. Interest also accrues on any tax owed. Filing late is better than not filing — do it as soon as possible and check AT notifications for any demand.
When are IRS refunds or payments due in Portugal?
AT typically issues IRS assessments (nota de liquidação) between July and September, after the filing window closes. Refunds follow the assessment and are paid to the IBAN registered in your Portal das Finanças account. Make sure your IBAN is correct before filing. If tax is owed rather than refunded, the payment deadline runs from the date of the assessment notice.
When do I have to pay IMI in Portugal?
IMI (Imposto Municipal sobre Imóveis) payment depends on the amount due. Bills under €100 are paid in a single instalment in April. Bills between €100 and €500 are split into two instalments: April and November. Bills over €500 are split into three instalments: April, July, and November. AT sends a payment reference to your Portal das Finanças.
When do I pay IUC vehicle tax in Portugal?
IUC (Imposto Único de Circulação) is due in the month of the vehicle’s first registration, not on a universal date. If your car was first registered in March, your IUC is due each March. You pay through the Portal das Finanças using the vehicle’s registration plate.
What is IRS Automático and should foreigners use it?
IRS Automático is AT’s pre-filled return for taxpayers with simple income situations — typically only Portuguese-source employment or pension income, no foreign income, and no special tax regimes. Most foreigners should not rely on it without verification. Foreign income, NHR/IFICI status, rental income, and capital gains all require Modelo 3 instead.
What tax deadlines apply to recibos verdes workers?
Self-employed workers on recibos verdes have several additional obligations: monthly Segurança Social contributions (generally due by the 20th of the following month), and quarterly declarações trimestrais (activity declarations) due in January, April, July, and October. They must also file annual IRS via Modelo 3 with Annex B, and their e-Fatura invoices include both personal expenses and business-related invoices that should be separated.
If you are in the IRS filing window now, open Portal das Finanças and check your pre-filled return before confirming anything. The IRS Portugal guide for foreign residents covers what to look for in Modelo 3 and when to bring in a tax adviser.