HMRC forced banks and building societies to hand over information about UK taxpayers with potential undeclared income in offshore bank accounts.
Other third-party companies are now also obliged to disclose such details.
The initial offshore amnesty; the offshore disclosure facility (ODF) ran from April 2007 to June 2007 and, as a result of this opportunity, around 40,000 UK taxpayers volunteered information raising £400 million in tax.
A second amnesty; the new disclosure facility (NDF) ran from September 2009 to January 2010. It is believed that only about 13,000 people are thought to have come forward during this amnesty.