National Irish Bank and An Post have come to an agreement that will see the bank's customers able to lodge and withdraw cash at more than 1,200 post offices throughout the country.
Customers will also be able to lodge cheques at post offices.
National Irish Bank chief executive Andrew Healy said the move was part of a series of changes it was planning. The banks has already begun a restructuring programme announced late last year, which will see its branches stop handling cash transactions.
The new service with An Post will be offered from the end of the year. The bank's customers will still be able to lodge cheques at National Irish Bank branches.
The bank is on track to close 25 of its 58 branches in the Republic. Some three of the 25 branches earmarked for closure have shut down. Staff numbers will reduce by 150 – or 25 per cent – by mid-2011.