The Revenue Commissioners has launched an investigation into the use of trusts and offshore structures, to see if they have been used by Irish residents to avoid paying tax.
The revenue will not put a figure on how much unpaid taxes it expects to uncover, but says the amounts could be substantial.
A voluntary disclosure scheme, which includes a number of benefits for those who avail of it, will be available until 1 September.
According to the revenue, the benefits of voluntary disclosure include a substantially reduced penalty on underpaid taxes.
Defaulters will also avoid having their name included on the quarterly list published in Irish Oifigúil, and no prosecution will be taken against the individuals concerned.
Under the most recent Finance Act, new obligations were put on third-party professionals dealing with tax affairs, including accountants, tax practitioners, solicitors, banks and other financial institutions, to report all transfers of property, assets and funds made into offshore trust structures to the revenue since December 2003.
The obligation falls on those, who through their trade or professions, have been involved in making an offshore transaction with a trust for someone who lives in Ireland for tax purposes.
As a result of the legislation, the revenue will shortly begin receiving details of the identities of people who have made transfers through trusts over the past five years since 24 December 2003.
They will also get details of the identities of the non-resident trustees and the dates that the transactions took place.
This information will be used to identify and pursue, where necessary, people who have used trusts and offshore structures to avoid paying tax and who have not declared them for tax purposes.
The revenue says it has become aware of the possible use of such trusts for tax evasion purposes through its other recent special investigations and initiatives.
It says they are one of the last hiding places for tax evaders in this country.
