Former Taoiseach Brian Cowen's consultancy company made a €17,000 profit in its first year of trading.
Mr Cowen, who was leader of the country when the economy collapsed, set up the company with his wife Mary two years ago.
Accounts filed with the Companies Registration Office (CRO) show the firm made a profit of €17,498 last year.
Cowen Consultancy Ltd's accounts also record €12,000 in cash and a further €19,000 worth of stock.
Mr Cowen, who is due to appear before the Oireachtas Banking Inquiry in the coming months, has 99 shares in the company and his wife has one.
Documents filed with the CRO said the firm provides "business and consultancy services, and any other related activities".
In 2012, Mr Cowen enrolled in California's Stanford Graduate School of Business to take part in an executive training programme where he was lectured by former US Secretary of State Condoleezza Rice, among others.
The former Taoiseach is a non-executive director of Topaz Energy Group Ltd and a director of Beacon Hospital Sandyford Ltd.
The Dáil recently heard Mr Cowen and former Taoiseach Bertie Ahern both received ministerial pensions worth more than €80,000 last year.
During the summer, Mr Cowen will give evidence over two days to the Banking Inquiry on his role in the events leading up to the bank guarantee.
Mr Cowen, who has made very few public appearances since leaving office, has welcomed the opportunity to speak before the inquiry.
Speaking last month, the former Taoiseach said he was "furious" with Central Bank Governor Patrick Honohan's suggestion that he overruled the late Brian Lenihan, the then Finance Minister, on the night of the guarantee in 2008.