Before opening the return, answer three questions: what was your residence status, which income belongs in each period, and which records support it? This article helps you prepare those decisions. For the submission workflow, use the first Modelo 3 guide alongside the interactive checklist.
Updated 15 September 2026. Editorial check against official sources. Professional review has not been recorded.
Start with a dated residence timeline
Write down your arrival and departure dates, overnight stays, when a home became available and your residence position in the previous year. Keep the supporting records beside the timeline.
The official residence rules include more than 183 days in a relevant rolling 12-month period and a habitual-home test that can apply with fewer days. A visa, NIF, late arrival or address registration is not a complete residence assessment. See the tax-residency guide for the tests, start-date exceptions and treaty questions.
If your status changed during the year, use the arrival-year guide. Under article 57(6), resident and non-resident periods require separate declarations where the filing obligation applies. Non-resident periods generally concern Portuguese-source income; resident periods generally concern worldwide income. Check exemptions and any applicable treaty or special regime before concluding what must be declared.
Build an income schedule before choosing annexes
For each income stream, note the person, income type, relevant dates, gross amount, currency, country of source and tax paid. Keep the net receipt as a separate reconciliation figure.
A foreign bank account or overseas employer does not automatically make income foreign-source. Work performed in Portugal needs its own source analysis. The Anexo J guide explains this distinction and the separate questions about foreign accounts.
Start collecting the records with our five-group document guide. It covers evidence, currency conversion, portal access and bank details without assuming your foreign annual return maps directly to Portugal's forms.
Identify the questions that need a decision
Use a short list rather than leaving uncertainty hidden in a spreadsheet. For example:
- Which date starts the resident period, and what evidence supports it?
- Was employment exercised in Portugal, abroad or both?
- Is a foreign tax figure final, withheld or still estimated?
- Does a treaty or registered special regime affect this particular income?
- Are both members of a couple in the same residence position?
Do not put a guessed answer into the return merely to get past a field. Use the relevant official instructions, ask AT a procedural question or obtain advice for a fact-specific position.
Check the deadline for the return you are preparing
The ordinary electronic filing window in CIRS article 60 is 1 April to 30 June. The article also provides a conditional 31 December extension for qualifying foreign tax that remains undetermined, requiring timely notification to AT. It is not a general extension for every foreign-income filer.
For the 2027 filing season, distinguish this current statutory framework from campaign-specific forms, codes and preparation dates that still need checking when published. If a deadline has already passed, establish the appropriate filing or correction procedure promptly rather than relying on a generic penalty estimate.
Move from preparation to submission
Once the residence position and records are ready, follow the Modelo 3 guide through access, annex selection, review, validation and submission. Keep proof of submission and check the subsequent processing status; saving a draft is not filing a return.
Use the first-filing checklist for an orderly final check. It helps track the work, but it does not calculate your liability or establish that your tax treatment is correct.
These resources provide general information and do not accept tax filings.