Bank of Ireland has announced pre-tax losses of 2.1 billion euro (£1.8 billion).
The bank blamed the massive increase in losses, up from 190 million euro (£164 million) in 2011, on the impairment charges it has been hit with.
Its report for 2012 revealed losses of 1.7 billion euro (£1.4 billion) on asset sales, redundancy charges, and buying back its subordinated bonds.
Some 5,000 members of staff have left the bank on a special redundancy programme enforced after Ireland's banking collapse.
The bank said its impairment charges were 11% lower than in 2011.
A further breakdown of figures showed areas where impairment charges were hitting hardest, with losses for the residential mortgage sector of 462 million euro (£399 million) and property and construction at 797 million euro (£689 million).
The Irish state owns 15% of Bank of Ireland.
Bank of Ireland group chief executive Richie Boucher said that, while the economy has improved recently, the environment remains difficult and the bank continues to face many challenges.
"Bank of Ireland has made good progress against our strategic objectives as we enhance our core franchises and rebuild profitability within a restructured, robust balance sheet, in what was another challenging year for the group," he said.