Ireland has two sets of mandatory disclosure rules – the domestic Mandatory Disclosure rules for aggressive tax planning (the domestic regime) and the cross-border rules introduced by EU Directive 2018/822 regarding mandatory exchange of information regarding certain reportable cross border arrangements (the cross-border regime).
The domestic regime requires a promoter of disclosable transactions to provide specified information to Revenue within 5 days of the earlier of the first marketing contact, the date the scheme is made available for implementation, or the date the promoter is first aware that any part of the disclosable transaction has been implemented. A promoter is anyone who designs, markets or organises or manages a disclosable transaction, or is otherwise responsible for the organisation or management of that transaction.  If there is no promoter, if the promoter is outside the State, or if the promoter claims legal and professional privilege then the reporting obligation shifts to the person who participates in the disclosable transaction.
The cross-border regime requires an intermediary to a reportable cross border arrangement to provide specified information to Revenue within 30 days beginning on the earlier of the day after the reportable cross border arrangement is made available for implementation, the day after the reportable cross border arrangement is ready for implementation, or when the first implementation step is taken. An intermediary is an individual or entity who designs, markets organises or manages, or makes available a reportable cross border arrangement. They must be resident or have a permanent establishment in a Member State, be incorporated or governed by the laws of a Member State, or be registered with a legal, tax or consultancy professional body in a Member State. If there is no intermediary, or if the intermediary claims legal and professional privilege then the reporting obligation shifts to the person who participates in the reportable cross border arrangement or to whom the reportable cross border arrangement is made available. Avoidance of CRS reporting falls under the cross-border regime.
Under both regimes, a transaction or arrangement that is reported to Revenue is given a unique reference number which must be included on the tax return of the person who entered into the transaction (cross-border regime only) or the person who obtains the tax advantage.
Revenue can impose penalties on those who fail to comply with their obligations under either regime.