The internal audit function is performed by the Audit Department and supervised by the Board of Auditors of Banco de Portugal.

The Audit Department aims to improve the effectiveness of risk, control and internal governance processes of the Bank. This department's responsibilities are contained in the Banco de Portugal Internal Audit Charter, approved by the Board of Directors.

The Board of Auditors ensures that the internal audit function is performed in an independent, systematic and effective way and contributes to the achievement of the Bank's mission and goals. 

The Audit Department also participates in the internal audit of the Eurosystem and European System of Central Banks (ESCB), according to the policy and procedures approved by the Governing Council of the European Central Bank (ECB).

The internal audit policy in place at Eurosystem/ESCB level is set in the document 'Audit Charter for the Eurosystem/ESCB and the Single Supervisory Mechanism'.