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Personal Portuguese Tax Calendar 2026/2027

Personal Portuguese Tax Calendar

Tick your profile and see, in date order, only the tax deadlines that concern you over the next 12 months — IRS, VAT, IMI, vehicle tax and Social Security. With what happens if you miss each one, a guide to which IRS annexes you need, and export to your own calendar. All in your browser.

By Elijah · UPDATED JULY 2026 ·4 MIN ·OFFICIAL SOURCES
KEY FACTS
IRS filing (Modelo 3)
1 April to 30 June
Validate invoices (e-fatura)
Until 25 February
IRS refund
AT pays by 31 August
Vehicle tax (IUC)
In your plate’s month
O SEU PERFIL
OS SEUS PRÓXIMOS 12 MESES
Marque pelo menos um perfil acima para ver os seus prazos.
DE QUE ANEXOS DO IRS PRECISA?

How this works

Each year the tax authority publishes the Fiscal Agenda — the calendar of every obligation. This tool filters that agenda to your situation: pick who you are and see only your deadlines, in date order, with a note of what happens if you miss each one.

  1. 1
    Pick your profile, see only your deadlines
    The tax authority’s official calendar has dozens of obligations, most of which do not apply to you. Tick who you are — employee, freelancer, landlord, homeowner, car owner — and the tool shows the list, in date order, with only the deadlines that concern you over the next 12 months.
  2. 2
    Dates from the official agenda, weekend-adjusted
    Dates follow the AT’s 2026 Fiscal Agenda and Social Security rules. When a deadline lands on a Saturday or Sunday, the obligation moves to the next working day — the tool makes that adjustment. For 2027, some dates follow the statutory rule while the 2027 agenda is unpublished; those are flagged.
  3. 3
    IUC depends on your plate’s month
    The vehicle circulation tax (IUC) is paid each year by the end of the month in which the car was first registered. Enter that month and the right date appears in your list. IMI depends on the amount: up to €100 it is paid once in May; up to €500, in May and November; above that, in May, August and November.
  4. 4
    Which IRS annexes do I need?
    The Modelo 3 return carries annexes depending on your income: Annex A (employment), B (self-employed, simplified regime), F (rents), G/G1 (capital gains), H (deductions — health, education), J (foreign income) and L (non-habitual resident / IFICI). The quick guide below tells you which to tick.

Frequently asked

When is the IRS filing deadline in 2026?
The IRS Modelo 3 return is filed between 1 April and 30 June, whatever your type of income. The deadline is the same for everyone — the old split by income category is gone. Filing late is possible but triggers a penalty. Any refund is paid by the tax authority by 31 August.
Why do I have to validate invoices in February?
The expenses that earn IRS deductions (health, education, care homes, property) are collected by the e-fatura system through the year, but some stay “pending”, waiting for you to confirm which sector they belong to. You have until 25 February to do this on the Finanças portal; after that the deduction totals are locked and are the ones that appear in your pre-filled return.
I’m a freelancer (recibos verdes). What deadlines do I have?
Besides the IRS in April–June (with Annex B): the quarterly Social Security declaration is filed on the last day of January, April, July and October; the monthly contribution is paid by the 20th of the following month. If you are in the VAT regime, you file the periodic return (monthly or quarterly) and pay the VAT. You may also owe IRS payments-on-account in July, September and December. Tick “Freelancer” to see your dates.
When do I pay IUC and IMI?
IUC (car tax) is paid each year by the end of the month your vehicle was first registered — if the plate is from March, you pay in March. IMI (property tax) for the previous year is paid in May if it is up to €100, in May and November if up to €500, and in May, August and November if above €500.
What happens if I miss a deadline?
It depends. A late declaration (IRS, VAT) triggers a fine that can be reduced if you fix it quickly and on your own initiative. A missed payment accrues late-payment interest. In many cases it is worth asking to pay in instalments or regularising before the tax authority opens a case. The tool gives a risk note on each line.
Are the 2027 dates final yet?
Dates up to the end of 2026 follow the AT’s official Fiscal Agenda. Those in 2027 follow the statutory rule (same day of the month, weekend-adjusted), but the official 2027 agenda is only published at the end of 2026 and the tax authority sometimes extends deadlines by order. The 2027 rows are flagged “statutory rule” — always confirm on the Finanças portal near the date.
OFFICIAL SOURCES
DISCLAIMER
An informational tool with no official standing. Dates follow the AT’s 2026 Fiscal Agenda and the Social Security rules known in July 2026; the 2027 dates follow the statutory rule while the official agenda is unpublished. The tax authority can extend deadlines by order and there are specific obligations not listed here. Always confirm on the Finanças portal or Segurança Social Direta before each date. Not tax advice.