Incorrectly recorded staff taxi runs, meals and other claims have left Leinster House bosses facing an embarrassing 333,412 euro tax settlement.
Part of the accounting blunder was voluntarily disclosed to the Revenue Commissioners in December 2012 after the powers-that-be in the Houses of the Oireachtas looked into the use of cabs dating back three years to January 2010.
The settlement for under-declaration of PAYE and PRSI was detailed in the latest defaulters list.
In a statement, the Oireachtas, which employs 378 civil servants to ensure the smooth running of the Dail and Seanad, said the analysis of taxi use had been taken as part of commitments to best corporate practice and governance and ongoing oversight of expenditure.
The Houses of the Oireachtas Service has had an ongoing practice to provide taxis to staff who stay late to perform official functions for the Houses of the Oireachtas, it said.
During analysis of all trips taken during the course of the last three years it was apparent that many taxis taken from work to home were taken outside of Revenue-allowable taxi journeys.
The disclosure prompted Revenue to audit the Oireachtas in February 2013 and issue a set of revised calculations based on all non-business journeys, all journeys from home to work, all journeys from work to home before 10pm and all journeys for people who made more than 60 journeys a year even if they were after 10pm.
The voluntary disclosures found 119,205 euro in tax for benefit in kind taxi use, 17,019 euro interest and 35,761 euro of penalties and 1,168 euro of VAT fell to be paid by the Oireachtas.
There were additional liabilities which included 106,912 euro for tax, interest and penalties on meal allowances; 41,445 euro for tax, interest and penalties related to employment status; 4,940 euro for benefit in kind car use; 3,143 euro for benefit in kind car sales; and 4,985 euro for honoraria or ex-gratia payments.
The Revenue calculated the tax settlement as 227,910 euro in unpaid tax, 37,128 euro in interest and 68,373 euro in penalties.
None of the issues identified related to politicians, their work or expenses.
It was one 131 settlements worth 23.25 million euro completed in the first three months of the year with the Revenue and published in Irish Oifigiuil.
The largest on the list involved retired medical consultant Maurice Fenton, of Cunningham Road, Dalkey, Co Dublin, who agreed a settlement of 2.6m euro in tax, interest and penalties for under-declaration of income tax and capital gains tax.
Other million-plus settlements included Clare Campbell, a retired guest house owner from St Mary s Road, Ballsbridge, Dublin who agreed to pay 2.2m euro for under-declaration of Capital Gains Tax and Robert Campbell, an employee, with the same address who settled for 555,000 euro for the same reason.
Revenue said that out of the 113 published cases, 48 were for amounts exceeding 100,000 euro and 13 of those were worth more than 500,000 euro.