The legal framework for the Eurosystem’s minimum reserve system is enshrined in Article 19 of the Statute of the European System of Central Banks (ESCB Statute), the Council Regulation (EC) on the application of minimum reserves by the European Central Bank and in the ECB Regulation on the application of minimum reserves.
Article 19.1: Subject to Article 2, the ECB may require credit institutions established in Member States to hold minimum reserve on accounts with the ECB and national central banks in pursuance of monetary policy objectives. Regulations concerning the calculation and determination of the required minimum reserves may be established by the Governing Council. In cases of non-compliance the ECB shall be entitled to levy penalty interest and to impose other sanctions with comparable effect.
Article 19.2: For the application of this Article, the Council shall, in accordance with the procedure laid down in Article 42, define the basis for minimum reserves and the maximum permissible ratios between those reserves and their basis, as well as the appropriate sanctions in cases of non-compliance.
Implementing the ECB Regulation on the application of minimum reserves ensures that uniform conditions for the Eurosystem's minimum reserve system prevail throughout the euro area.