Every deadline a Portuguese company lives by, counted from today
Invoice data on the fifth, VAT on the twentieth, payroll on the tenth, two annual filings and three payments on account. Written as a list it looks manageable; counted properly it is anywhere from about forty dated obligations a year to well over a hundred. Below is the 2026 agenda exactly as the tax authority published it — including the August gap and the extension most lists still have not noticed — sorted by what is actually next.
Tell it what kind of company you are, and it sorts by date
Every day below is the number printed in the tax authority’s 2026 summary tables, not a general rule we inferred. The countdown uses your own device’s date.
Obligations on these answers: — across 2026, of which — are still ahead.
Dated obligations per month. The highlighted month is the one you are in.
Turn the employee switch off and watch more than half the year disappear — on a monthly-VAT profile the count drops from 89 to 41. That is the honest answer to “how much admin is a Portuguese company?” — it depends almost entirely on whether anyone is on the payroll, and only secondarily on how much you sell.
The dates that are not what you think
The 2026 agenda leaves the August column empty for both the monthly VAT return and its payment. The June period moves to 21 September, paid on the 25th, landing next to the second-quarter filing for quarterly filers. A quiet August is followed by a September with two VAT events in it, and that is where the direct debit fails.
The most missed date of the yearThe ordinary deadline is the end of May. For 2026 the tax authority published 30 June, under Despacho 81/2026-XXV of 17 June. These extensions come most years and are announced late, which is exactly why a printed list goes stale: the rule did not change, the date did.
Plan for May, file by whatever they publishThe authority’s note says that in months ending at a weekend or on a holiday the obligation may be met on the next working day. That is about month-end deadlines. For mid-month ones the agenda simply prints a different day in that month’s cell — the payroll declaration is the 12th in January, withholding is the 22nd in June. There is no blanket rule to lean on.
Read the month, not the ruleDecreto-Lei 127/2025 moved the contribution payment window from the 10th–20th to the 1st–25th, with effect from January 2026, and replaced the monthly remuneration declaration with a confirmation due by the 20th. Any guide still saying the 20th is quoting the previous article 43.
Compulsory for all from January 2027A monthly rhythm with two annual events attached
People picture Portuguese compliance as an annual return with some paperwork around it. The shape is the other way round.
| Cadence | What falls due | Day | Applies to |
|---|---|---|---|
| Every month | Invoice data communication | 5th | Every company |
| Every month | Payroll declaration to the AT | 10th | With staff |
| Every month | Withholding tax paid over | 20th | With staff |
| Every month | Social Security confirmation / payment | 20th / 25th | With staff |
| Every month | VAT return and payment | 20th / 25th | Monthly regime |
| Every month | Modelo 30, payments abroad | Month end | Paying non-residents |
| Quarterly | VAT return and payment | Feb, May, Sep, Nov | Quarterly regime |
| Three times | Payment on account of corporate tax | 31 Jul, 30 Sep, 15 Dec | Every company |
| Once | Modelo 22, corporate tax return | End of May, 30 Jun in 2026 | Every company |
| Once | IES | 15 July | Every company |
Days shown are the rule. The calculator above carries the actual 2026 day for each month, which differs in roughly a quarter of cases.
The practical consequence is that a Portuguese company cannot really be run from an annual conversation with an accountant. Something is due in every single month of the year, and in most months it is three or four separate things with three or four separate dates. Firms that get into trouble here rarely do so because they misunderstood a rule. They do it because nobody owned a calendar.
What is not in the calendar above
- Invoice data communication, VAT both regimes, recapitulative statement
- Payroll declaration, withholding payment, Social Security confirmation and payment
- Modelo 22 and the tax balance, IES, the three payments on account
- Modelo 30, Modelo 10, the additional payment on account, property tax instalments
- The dossier fiscal — it does not appear in the authority’s summary tables, so we have published no date for it rather than guess one
- The annual inventory statement, stamp duty returns and sector-specific filings
- Anything triggered by an event rather than a date: hiring, a capital change, a property purchase
- Companies whose tax period does not coincide with the calendar year, for which every annual date shifts
- Autoridade Tributária e Aduaneira, Agenda Fiscal 2026 — the summary tables of declaration obligations and of payment obligations, from which every day on this page is taken.
- Despacho n.º 81/2026-XXV, de 17/06 — the extension of the Modelo 22 deadline and of the corresponding payment to 30 June 2026; Despachos 166/2025-XXV, 40/2026-XXV and 55/2026-XXV for the invoice-communication extensions in January, April and May.
- Decreto-Lei n.º 127/2025, de 9 de dezembro — the new contributory model: contributions paid between the 1st and the 25th, monthly confirmation by the 20th with silence as acceptance, compulsory for all employers from 1 January 2027.
One note on how we read the source. The authority’s tables carry a single note about weekends: that in months ending at a weekend or on a holiday, the obligation may be met on the next working day. Mid-month collisions are handled by printing a different day rather than by a stated rule. We have followed the printed days and have not generalised the note beyond what it says.
What owners ask in their first year
What are the main annual deadlines for a Portuguese company?
Two filings dominate the year. Modelo 22, the corporate tax return, is ordinarily due at the end of May — for 2026 it was extended to 30 June by despacho. IES, the simplified business information, is due on 15 July. Payments on account of corporate tax fall three times: 31 July, 30 September and 15 December 2026. Everything else is monthly or quarterly.
When is VAT due?
For the monthly regime, the return is filed by the 20th of the second following month and paid by the 25th. For the quarterly regime the same days apply, in February, May, September and November. Both dates shift in individual months of 2026 where the 20th or 25th falls at a weekend.
Why is there no VAT deadline in August?
Because of the August concession. There is no monthly VAT filing in August at all in the 2026 agenda — the June period moves to 21 September, with payment on 25 September, alongside the second quarter for quarterly filers. It is the single most missed date in the Portuguese year, because a month with nothing due is followed by a month with two things due.
When do I have to communicate invoice data?
By the 5th of the following month as a rule. In 2026 the actual days were 9 January, 5 February, 5 March, 8 April, 8 May, 5 June, 6 July, 31 August, 7 September, 6 October, 5 November and 7 December — the departures are weekend rolls plus three formal extensions granted by despacho.
What changed for Social Security in 2026?
Two things, under Decreto-Lei 127/2025. Contributions are now paid between the 1st and the 25th of the following month rather than the 10th to the 20th, and the monthly remuneration declaration is being replaced by a confirmation: the system computes from the permanent remuneration declared at hiring and you confirm or correct by the 20th, with silence counting as acceptance. The new model is compulsory for every employer from 1 January 2027.
What happens if a deadline falls at a weekend?
Less automatically than people assume. The tax authority’s note says only that in months ending at a weekend or on a holiday, the obligation may be met on the next working day — that covers month-end deadlines. For mid-month deadlines the agenda simply prints a shifted day in that month’s cell. So the right answer is to read the published day for the month in question rather than apply a general rule.
Is Modelo 22 due in May or June?
The ordinary statutory deadline is the end of May. For 2026 the tax authority published 30 June, under Despacho 81/2026-XXV of 17 June. Extensions like this are granted most years but are not guaranteed, so the safe planning assumption is May and the actual date is whatever the agenda says that year.
Which of these apply to a company with no employees?
The payroll declaration, the withholding payment and the Social Security confirmation all fall away, which removes roughly a third of the calendar. What remains is invoice communication, VAT, the two annual filings and the payments on account. Use the switches above — the count at the bottom changes with them.
None of this needs your attention if somebody owns it
Every date on this page is somebody’s job, and it is not a good use of a founder’s month. We keep the calendar, file on the published day rather than the remembered one, and tell you in advance only about the ones that need a decision from you — the payments on account, the balance in June, and whether the August gap is going to catch your cash flow.