With the resolutions "under the Swiss Bank Program, the department has reached agreements with 75 Swiss banks, imposed penalties in excess of $1 billion, and secured voluminous and detailed information regarding the illegal conduct of financial institutions, professionals and account holders around the world", said Caroline Ciraolo, acting assistant attorney general in the Department of Justice's tax division.
The program, started in August 2013, allows non-prosecution agreements for banks that agree to cooperate with probes, pay fines for tax-related criminal offences and provide account-specific information on US taxpayers.
The program is closed to banks such as Credit Suisse that were already under criminal investigation for enabling tax evasion at the time of the program's inception.
The data from the program has enabled investigators to "track those individuals who think they are above the law and continue to hide their money offshore," said Richard Weber of the criminal investigation division of the Internal Revenue Service.
The banks covered in the latest round of settlements are Bank J. Safra Sarasin, Coutts & Co., Gonet & Cie and Banque Cantonal du Valais. The four banks collectively will pay more than $178 million in penalties.