Single Supervisory Mechanism


The participants in the Single Supervisory Mechanism (SSM) are all the countries that form part of the Eurosystem and all European Union countries which are not in the euro area, but which want to establish a close cooperation with the European Central Bank (ECB) and therefore accept this new supervision system. To date, no country outside the euro area has officially asked to join the SSM.

The ECB directly supervises institutions which are considered to be significant, while all other less-significant institutions are directly supervised by national competent authorities (NCAs), and indirectly supervised by the ECB.

The criteria determining whether an institution is significant are:

  • Its consolidated total assets are worth over 30 billion euros.
  • Its assets are worth more than 20% of the GDP of the country in which it is established, unless the consolidated total assets are less than 5 billion euros.
  • It is one of the three largest credit institutions in a member state.
  • It has subsidiaries in more than one participant country, with cross-border assets or liabilities representing more than 20% of its total assets and liabilities.
  • It has requested or received public financial assistance from the European Stability Mechanism or the European Financial Stability Facility.

Based on these criteria, a list of significant institutions is periodically updated. Currently this list includes 126 significant institutions which represent almost 85% of total banking assets in the euro area, 14 of which are Spanish. In the case of Spain, the significant institutions which are directly supervised by the ECB represent around 95% of deposit institution total assets.