Permanent TSB has raised €500m of five-year debt at a cost of approximately 0.25%.
The debt was raised through a securitisation of residential mortgage backed securities.
The bank said the offer was oversubscribed by around 2.5 times and priced at three-month Euribor + 55bps (equivalent to 0.25%).
Interim Group Treasurer Declan Dolan said the offer had met an extremely positive market reaction.
He added: “This is the first public RMBS sale undertaken by the Group in almost three years and is another very significant step in re-shaping the Group's Balance Sheet.
“We have raised €500m of five-year funding at an equivalent rate of approximately 0.25%.
“This will improve the Group's Liquidity and Capital regulatory ratios and will also support planned mortgage lending growth.”
The State owns just under 75% of Permanent TSB, having reduced its shareholding down from above 99% last year.