Sometime in the past two decade the developed countries decided to share a large amount of the financial informations of its residents. Buzzwords were anti-terror, crime, narcotics, corruption, etc. The Organisation for Economic Co-operation and Development (OECD) countries have committed to exchange bank data among themselves. As of now, the OECD Common Reporting Standard (CRS) is the global standard for the Automatic Exchange of Information countries. The Automatic Exchange of Information (AEOI) has become a reality since 1 January 2017.
This most money people already knew, but that an Automatic Exchange of Financial Account Information would be applied retroactively, very few were aware of. Since January 1, 2017, Swiss banks have been systematically collecting bank data from customers who are tax resident in the 38 contracting states (OECD AEOI CRS countries). These data are to be exchanged for the first time with 38 states in September 2018. The system was designed among the lines of the Foreign Account Tax Compliance Act (FATCA), which requires most countries to share financial data with the US.
This means that if you aren’t a Swiss citizen, the days of your banking secrecy are over. A long ago.