Method and sources: Portugal

Every rate and amount comes from an official source.

How we calculate

• We calculate what appears on the payslip: IRS withholding from the official tables in force in the month of payment, and the worker’s Social Security contribution.
• Withholding follows the despacho formula: pay × maximum marginal rate − amount to deduct − extra amount per dependant, never below zero. With three or more dependants the rate drops by one percentage point.
• Holiday and Christmas subsidies are always withheld separately (CIRS art. 99.º-C). If paid in twelfths, each month withholds the proportional part.
• Net to gross uses the engine itself: a binary search finds the smallest gross that gives the net pay requested.

Official sources

• Despacho 233-A/2026

  Mainland withholding tables and calculation rules. Checked on October 30, 2026

• Despacho 12523-A/2026

  November 2026 withholding adjustment (mainland). Checked on October 30, 2026

• Despacho 12610-A/2026

  November 2026 withholding adjustment (Azores). Checked on October 30, 2026

• Tax Authority Circular 3/2026

  Azores withholding tables (Despacho 1179/2026). Checked on October 30, 2026

• Declaração de Retificação 10/2026 (JORAM)

  Madeira withholding tables (Despacho 19/2026, as rectified). Checked on October 30, 2026

• CIRS, article 12.º-B

  IRS Jovem: exemption shares and cap. Checked on October 30, 2026

• CIRS, article 99.º-C

  Withholding on holiday and Christmas subsidies. Checked on October 30, 2026

• CIRS, article 99.º-F

  Withholding tables and IRS Jovem withholding. Checked on October 30, 2026

• Portaria 480-A/2025/1

  The 2026 IAS value, which sets the IRS Jovem cap. Checked on October 30, 2026

• Social Security Contributions Code, article 53.º

  The 11 % worker contribution rate. Checked on October 30, 2026

What we do not cover

• The annual IRS assessment (deductions, aggregation, refund or tax due).
• Overtime, pensions, dependants or spouses with a disability and full-rate withholding.
• Civil servants’ pay and special Social Security regimes.