AL tax calendar for 2026: every deadline you cannot miss
Modelo 30, IRS, SIBA, RNAL, TMT — every AL obligation has its deadline. Here's your month-by-month calendar for 2026, all in one place.
Running a short-term rental in Portugal is, in large part, about managing deadlines. The problem is that AL obligations are scattered across different laws, different portals, and different authorities — and none of them will send you a friendly reminder when a date is approaching.
This article pulls the main annual obligations for a Portuguese AL host into one place. It's not an exhaustive guide to Portuguese tax law — it's a practical reference for what a rental owner actually needs to track throughout the year.
Important note: Tax deadlines can be adjusted by ministerial order during the year. Always confirm final dates on the Autoridade Tributária (AT) portal and in the Diário da República before acting. This article reflects the general framework currently in force — it is not a substitute for professional tax advice.
What you need to manage, and why
Before getting into the calendar, it helps to understand the four main categories of obligations:
- Tax (AT): income declarations, withholding tax, reporting of income paid to non-residents.
- Registration and licensing (RNAL): keeping your entry in the Registo Nacional de Alojamento Local current, including renewals and data updates.
- Guest data and security (SEF/SIBA): submitting guest identification data to the relevant authorities.
- Municipal tourist tax (TMT): the local tourist levy, which varies by municipality and comes with its own reporting cycles and deadlines.
Each category runs on its own rhythm. Let's go through them.
First quarter — starting the year without loose ends
January
The start of the year is the moment to close out the previous one. If you made payments to non-resident entities — for example, commissions to foreign platforms such as Airbnb Ireland or Booking.com B.V. — you may have withholding tax obligations and a duty to report those payments to AT via Modelo 30.
Modelo 30 is used to declare income paid or made available to non-resident entities. The exact frequency and deadlines depend on the volume and nature of the payments — check the AT portal or speak to your accountant to confirm whether this applies to you and when.
January is also a good moment to:
- Review your RNAL registration and confirm that all details are current (address, capacity, registered holder).
- Check whether your municipality charges a tourist tax and what the reporting cycle is — monthly, quarterly, or twice-yearly.
February and March
This period is typically quieter in terms of formal deadlines, but it's the right time to organise documentation from the previous year: rental receipts, invoices for deductible expenses, occupancy records. Arriving at April with everything in order makes a significant difference.
If you issue invoices through e-fatura — mandatory for AL — confirm that all 2025 invoices have been submitted and are error-free.
Second quarter — IRS season
April and May
This is the centrepiece of the Portuguese tax calendar: filing your IRS declaration for the previous year's income.
AL income can fall under different tax categories depending on how you operate — Category B (business and professional income) is the most common for individual hosts. Whether you use the simplified regime or organised accounting determines how your income is calculated.
The IRS filing window typically runs from April through to the end of June, but always verify the exact dates on the AT portal for the current year — they have shifted slightly from year to year.
During this period, you also need to make sure that:
- AL income is correctly declared in the appropriate annexes.
- Deductible expenses (maintenance, insurance, condominium fees, etc.) are documented and recorded.
- If you have co-owners or partners, the income allocation is correct.
June
Time to close out the IRS and prepare for summer — which for most hosts is the peak occupancy season and, therefore, the period of greatest exposure to ongoing obligations.
Third quarter — peak occupancy, peak obligations
July, August, and September
There are no major annual deadlines in this window, but it's when the most things can go wrong day to day.
SIBA (Sistema de Informação de Boletins de Alojamento): Reporting guest data to SEF (now AIMA — Agência para a Integração, Migrações e Asilo) is a continuous obligation, not an annual one. Each non-resident guest must be reported within the legal timeframe after check-in. Summer volumes go up — and so do the chances of errors slipping through.
Municipal tourist tax: If your municipality charges TMT, this is the quarter when you collect the most — and, depending on the reporting cycle, it may also be when you need to file and pay. Check the specific calendar for your municipality (Lisbon, Porto, Cascais, Sintra, Albufeira, and others each have their own rules).
Invoicing: Keep your e-fatura submissions up to date. Accumulated delays are not something the system forgives quietly.
Fourth quarter — closing the year properly
October and November
Some municipalities have twice-yearly tourist tax filings with an autumn deadline — check your local municipal regulation.
This is also a good moment to review your RNAL registration. If there were any changes to the property, its capacity, or the registered holder during the year, these need to be reflected in the register. Unreported changes can create problems at renewal time or during an inspection.
December
The month to take stock and prepare for the year ahead:
- Organise all 2026 documents for the 2027 IRS filing.
- Confirm there are no outstanding invoices to issue or submit.
- Check for any legislative changes affecting AL in 2027 — the State Budget is typically approved around this time and can bring changes to tax coefficients, rates, or registration requirements.
Quick reference: obligations by frequency
| Obligation | Frequency | Authority |
|---|---|---|
| Guest reporting (SIBA) | Continuous (per check-in) | AIMA |
| Electronic invoicing (e-fatura) | Continuous (per transaction) | AT |
| Municipal tourist tax (TMT) | Monthly, quarterly, or twice-yearly (varies) | Municipality |
| Modelo 30 (income to non-residents) | Monthly or when applicable | AT |
| IRS declaration | Annual (spring) | AT |
| RNAL registration update | When changes occur / at renewal | Municipality / RNAL |
The most common mistake: confusing "I didn't get a reminder" with "there's no deadline"
AT and the municipalities have no obligation to remind you of upcoming dates. The responsibility is yours — and the fines for non-compliance can be significant, particularly when there's a repeat offence or when a delay is picked up during an inspection.
The AL tax calendar isn't complicated, but it is spread out. The answer isn't to memorise everything — it's to have a system that alerts you before a deadline, not after.
A note on updates
This calendar reflects the general AL framework in Portugal. Exact deadlines are confirmed each year by AT and the municipalities — and they can change. We recommend keeping this article as a structural reference and verifying final dates from official sources at the start of each year:
- AT portal: at.gov.pt
- RNAL: rnt.turismodeportugal.pt
- Municipal tourist tax regulation: on your municipality's website