The Department of the Taoiseach has paid almost €25,000 to the Revenue Commissioners in a voluntary settlement.
Taoiseach Enda Kenny also disclosed that since 2011 almost €110,000 has been spent by the department's staff on taxis.
In response to a parliamentary question from Deputy Niall Collins, the Taoiseach revealed that the department had not been audited for tax compliance but last March an "unprompted voluntary disclosure" was made to the Revenue Commissioners.
It included liability for benefit-in-kind for the use of taxis to and from home of €24,506. This also included penalties and interest.
In his reply Mr Kenny said it related to the “long-standing practice where staff are sometimes required to work outside normal office hours to carry out official duties, in most cases due to Oireachtas sittings”.
The reply also revealed that since 2011 the Department of the Taoiseach has spent €109,203.15 on taxis.
Last year, the Taoiseach's department paid out over €28,000 on taxi costs.
It was noted, however, that this also included the period of the EU Presidency.
In 2011 the figure was over €41,000, and in 2012 the figure amounted to over €30,000 in taxi costs for staff.
This year, the department has spent just over €9,000 on taxis so far.
In his written reply, the Taoiseach said the department has put in place revised arrangements to ensure compliance with Revenue Guidelines in respect of benefit-in-kind on taxi journeys to and from home.