Revenues obtained by companies (corporate tax – IRC) or individuals (income tax – IRS) from Portuguese Government debt instruments (interest, redemption premia and other forms of income) are subject to  withholding tax.

Non-resident investors are exempt from withholding tax in Portugal, provided that:

• The income derives from securities (as Government Bonds or Treasury Bills)
  
  
•  The investor is not acting through a permanent company in Portugal
  
  
• The investor is not based in a tax haven.

The exclusion respecting holders that are resident in "tax havens" does not apply when the holder is a central bank or a governmental agency.

Financial institutions – Government debt interest is not subject to withholding tax when obtained by financial institutions: the interest is added to the company's income and taxed according to the corporate tax.

The interest on Saving Certificates and Treasury Certificates is subject to withholding  tax (income tax - IRS).

» Treasury Bills: Calculation Rule