Portugal’s annual IRS process covers several stages, from checking household information and deductible expenses to submitting the tax return and settling the final tax amount.

For the 2026 tax season, individuals are reporting income received during 2025. The main IRS filing period runs from 1 April to 30 June 2026, but some important tax deadlines fall before April.

Preparing the required information early makes it easier to identify missing invoices, incorrect household details or documents needed for specific income sources.

Portugal Tax Season: Key Dates for 2026

These deadlines relate to the 2025 tax year.

The annual IRS return is only one stage of the process. Check household information and e-Fatura records before the filing period begins.

What Tax Year Does the 2026 IRS Return Cover?

The 2026 IRS return generally covers income received between 1 January and 31 December 2025.

The return may include employment income, self-employment income, rental income, investment income, pensions and capital gains. The forms and annexes required depend on the types of income received.

Taxpayers with more than one income source should identify the applicable categories before starting the return and check any additional information on Portugal’s tax season. 

What Should You Check Before Filing IRS?

The preparation period begins before you can submit the annual return.

Two areas require particular attention: household information and e-Fatura records.

Check Household Information

Household details can affect certain IRS deductions.

Taxpayers should check their household and dependants' information, especially after events such as marriage, divorce, separation, or a child's birth.

For the 2026 tax season, the deadline for confirming relevant household information is 2 March 2026.

Check e-Fatura Invoices

Invoices recorded through e-Fatura can affect deductible expenses.

Check that invoices linked to your tax number are correctly recorded and assigned to the appropriate expense category. Missing or incorrectly classified invoices can affect the deductions taken into account when calculating IRS.

The deadline for confirming the relevant invoice information is 2 March 2026.

How Do You Check Portuguese Tax Deductions?

After the invoice confirmation period, taxpayers can review the deductible expenses the Portuguese Tax Authority records.

For the 2026 tax season, this review period runs from 16 to 31 March.

Depending on the expense, deductions can relate to areas such as:

• general household expenses;
• healthcare;
• education;
• rent and qualifying property costs;
• residential care;
• expenses supported by invoices.

If an amount is incorrect, the available correction procedure depends on the expense type.

You can also correct certain deductions through the annual IRS return using Annex H.

Retain supporting invoices and other relevant records, as you may need them to substantiate the amounts claimed.

What Happens When the IRS Filing Period Opens?

The annual IRS filing period runs from 1 April 2026 to 30 June 2026.

The annual return is submitted electronically using Modelo 3.

Before submitting it, taxpayers should check that they have included all relevant income and completed the required annexes. This is particularly important when the return includes foreign income, rental property, investments, self-employment or capital gains.

Who Needs to File an IRS Return in Portugal?

The requirement to submit a Portuguese IRS return depends mainly on tax residence and the type of income received.

Portuguese tax residents generally declare income from Portugal and other countries. Non-residents generally report taxable income connected to Portugal, subject to the rules that apply to the specific income.

Tax residence should be established for the relevant tax year. This is especially important for people who moved to or from Portugal during 2025, as their filing position may differ from someone who was resident for the whole year.

Which Types of Income Are Reported for IRS?

Portuguese IRS uses different income categories. The category determines how the income is reported and which information may need to be included with the return.

Employment Income

Employment income includes salaries, wages and other remuneration received from an employer.

Tax may already have been withheld during the year, but the annual IRS return determines the taxpayer's final position after accounting for income, withholding, and applicable deductions.

Self-Employment and Business Income

Income from professional activities and business activities generally falls under Category B.

Self-employed taxpayers may have additional records and reporting requirements, particularly when they provide services, issue invoices or carry out an independent business activity.

Organise income records and relevant business expenses before completing the return.

Rental Income

Income from renting property is generally reported under Category F.

Property owners should keep records of rent received and qualifying expenses connected with the rental activity.

The reporting requirements can differ depending on the nature of the rental activity and the taxpayer's residence status.

Investment Income

Interest, dividends and certain other investment returns may fall under Category E.

The applicable treatment depends on the income's nature and source, and whether tax has already been withheld.

Annual statements from banks, brokers and other financial institutions can help verify the figures reported on the tax return.

Capital Gains

Certain gains from selling or transferring assets fall under Category G.

This can include gains arising from property and securities transactions, as well as certain other transactions covered by Portuguese tax rules.

For a property sale, information about the acquisition, disposal and eligible associated costs may be required to calculate the taxable gain.

Pension Income

Pension income is reported separately from employment income.

People receiving pensions from outside Portugal should check the specific reporting requirements for foreign pension income, particularly if they are Portuguese tax residents.

How Is Foreign Income Reported in Portugal?

Portuguese tax residents generally need to include relevant foreign income in their Portuguese tax return.

Annex J covers several types of foreign income, including employment income, pensions, rental income, investment income, and business or professional income.

The information required depends on the type of income and the country where it arose.

Can Foreign Tax Paid Be Taken Into Account?

Tax already paid in another country may be relevant when calculating Portuguese tax.

Portugal's rules for avoiding double taxation can allow foreign tax to be taken into account, subject to the applicable rules and any relevant tax treaty.

Taxpayers should retain documents showing the foreign income and tax paid or withheld. These records can be important when completing the relevant sections of the Portuguese return.

What Documents Are Needed for a Portuguese Tax Return?

The documents required depend on the taxpayer's income and circumstances.

Common records include:

Personal and Household Records

Keep the information needed to confirm your tax identification details, tax residence, household status and dependants.

Employment and Pension Records

Employment and pension statements can help you check income received and tax withheld during the year.

Bank and Investment Statements

Bank, broker and investment statements can help verify interest, dividends and other investment income.

For foreign investments, records should also show the country involved and any tax withheld abroad.

Rental Property Records

Landlords should keep rental agreements, rent records, and invoices or other evidence of qualifying property expenses.

Property Transaction Records

For a property sale, keep documentation relating to both the acquisition and disposal of the property, together with records of relevant costs.

Foreign Tax Records

Taxpayers with foreign income should keep statements or certificates showing the income received and tax paid in the relevant country.

This documentation is especially important when Portugal considers foreign tax under its double-taxation rules.

What Happens After You Submit Your Portuguese Tax Return?

Submitting Modelo 3 does not necessarily mean the tax process is finished.

The Portuguese Tax Authority processes the declaration and issues a tax assessment showing the taxpayer's resulting position.

The assessment can show that additional tax is due, a refund is available, or the amounts already withheld cover the final liability.

Taxpayers should keep the submission confirmation and check the assessment once it becomes available.

When Is Portuguese IRS Tax Paid?

For returns processed under the standard timetable, the general IRS payment deadline is 31 August.

The amount payable is based on the final tax assessment. It may differ from the tax already withheld during the year because the final calculation accounts for the taxpayer's income and applicable deductions.

If the assessment is issued under different circumstances, a different payment deadline may apply.

When Are Portuguese Tax Refunds Paid?

For returns submitted within the normal filing period and processed under the standard timetable, the general refund deadline is 31 August.

The date the money reaches the taxpayer's account depends on how the return is processed.

Taxpayers expecting a refund should make sure their bank account information registered with the Portuguese Tax Authority is correct.

What Is Different for Non-Residents?

Non-residents are generally subject to Portuguese tax on Portuguese-source income, subject to the rules applicable to the particular type of income. This can affect people who live abroad but receive income connected with Portugal, such as income from Portuguese property. For non-residents managing Portuguese tax obligations, fiscal representation in Portugal can provide a point of contact with the Portuguese Tax Authority. 

This can affect people who live abroad but receive income connected with Portugal, such as income from Portuguese property.

Treatment depends on the source and nature of the income, not simply where the taxpayer currently lives.

People who changed their tax residence during 2025 should establish their status for the relevant period before completing the return.

Common Mistakes During Portugal’s Tax Season

Leaving the Return Until the Deadline

Starting the return on 30 June can leave little time to obtain missing documents or resolve discrepancies.

This becomes more difficult when several income categories or foreign income are involved.

Omitting Foreign Income

Tax already paid abroad does not automatically mean you can exclude the income from the Portuguese return.

Foreign income should be checked against the reporting requirements applicable to the taxpayer.

Not Checking e-Fatura

Incorrect invoice information can affect deductible expenses.

Checking records before submitting the annual return gives taxpayers a chance to identify problems early.

Using the Wrong Income Category

Portuguese IRS has different categories for different types of income.

Selecting an incorrect category or failing to include a required annex can result in an inaccurate declaration.

Overlooking Property Income

Rental income and gains from property transactions have specific reporting requirements.

Property owners should check these separately rather than assuming that property-related income is covered by other sections of the return.

Losing Supporting Documentation

Figures entered on the tax return should be supported by appropriate records.

Organise and retain invoices, contracts, bank statements, tax certificates, and transaction documents after filing.

What Should You Do Before the IRS Filing Deadline?

The most useful preparation is to work through the return before the filing window closes rather than treating 30 June as the starting point.

Check that all income records are available, identify the relevant IRS categories and confirm that the required annexes apply to your circumstances.

For more complex returns, review foreign income, property transactions, investment income and changes in tax residence separately. These areas often require additional information that may not be available from a standard employment statement.

How Can You Organise Your Portuguese Tax Documents?

A simple document structure can make the filing process easier.

Keep separate records for:

• employment and pension income;
• self-employment or business activity;
• rental properties;
• investments and bank accounts;
• property purchases and sales;
• foreign income;
• tax paid outside Portugal;
• deductible expenses.

For foreign income, keep the original amounts and the tax paid abroad rather than recording only the final amount received after foreign tax.

For property transactions, retain documents from both the purchase and sale. These may be needed when calculating a capital gain.

When Is Professional Tax Assistance Useful?

Professional assistance can be especially useful when a Portuguese tax return includes multiple income sources or cross-border elements.

Situations that may require additional tax review include:

• income from several countries;
• a change of tax residence;
• foreign pensions or employment income;
• Portuguese rental property owned by a non-resident;
• property sales;
• overseas investments;
• self-employment or business income;
• foreign tax paid during the year.

A professional review checks the applicable reporting requirements, income categories, and supporting documentation before you submit the return.

Portugal IRS Filing Checklist

Before 1 April

• Confirm household information.
• Check e-Fatura records.
• Review deductible expenses.
• Collect income statements.
• Organise investment and bank records.
• Gather property documents.
• Collect foreign tax certificates and income statements.

During the Filing Period

• Identify every relevant income category.
• Check which IRS annexes apply.
• Enter income and withholding amounts.
• Report applicable foreign income.
• Review deductions.
• Check the completed Modelo 3 carefully.
• Submit the return by 30 June 2026.

After Submission

• Save the submission confirmation.
• Check the tax assessment.
• Confirm whether additional tax is payable or a refund is due.
• Follow the applicable payment or refund procedure.
• Keep the supporting documentation.

How Early Should You Prepare for Portugal’s Tax Season?

For a simple return based mainly on employment income, preparation may take less time.

Returns involving foreign income, property, investments, self-employment or capital gains usually require more documentation. Starting several weeks before the filing period gives time to obtain missing statements and resolve discrepancies.

For the 2026 tax season, February and March are useful preparation months because you need to review household information, invoices, and deductible expenses before the main filing period begins.