Rural areas are set to be the big losers after Ulster Bank confirmed it is closing branches.
The bank confirmed that it is shutting 22 branches and laying off 220 people.
Most of the branch closures are in country towns, but five are set to go in Dublin.
The Dublin closures include relatively well-off places such as Dalkey, Donnybrook, Rathmines and Sandyford. Four branches are going in towns in Cork.
To counteract the closing of one-fifth of its branch network, the bank says that it will add two new mobile banks to its network.
It is aiming to achieve reductions in staff numbers through voluntary redundancies, but this cannot be guaranteed, it is understood.
The bank employs 2,810 people in branches and other roles.
There will be 88 branches left after the closures, which will take place in June and September.
Defending closures and lay-offs, the bank said it was seeing an average of just 30 customers a day using the branches it is closing.
Some 62pc of its transactions were digital last year. This compares with 10pc in branches, Ulster Bank said.
News of the branch closures was first reported in the Irish Independent earlier this month.
Ulster Bank chief executive Gerry Mallon said as well as doubling the number of mobile banks, the lender will introduce community bankers. These are officials who will help vulnerable customers to transact digitally.
The bank is also increasing its investment in its existing branches, he said.
Mr Mallon said closing a branch was a difficult decision which the bank did not take lightly.
"Our branch network remains an important part of how we serve our customers. However, the role of the branch continues to move towards advice and away from day-to-day transactions, with only 10pc of our customer interactions now happening in branch," he said.
The bank said it was consulting with the Financial Services Union (FSU) on the job losses.
The union expressed its opposition to closures and redundancies. "Ulster Bank in the Republic made a profit of €280m in 2016," senior industrial relations officer Gareth Murphy said.
Ulster Bank branches are closing in the following towns: Ardara, Co Donegal; Arva, Co Cavan; Ballincollig, Co Cork; Ballyhaunis, Co Mayo; Ballymote, Co Sligo; Blackpool, Co Cork; Briarhill, Co Galway; Carrickmacross, Co Monaghan; Carrigaline, Co Cork; Castletroy, Co Limerick; Cootehill, Co Cavan; Dalkey, Co Dublin; Donnybrook, Dublin; Dorset Street, Dublin; Edenderry, Co Offaly; Edgeworthstown, Co Longford; Fermoy, Co Cork; Newcastle, Co Galway; Newcastlewest, Co Limerick; Raphoe, Co Donegal; Rathmines, Dublin; and Sandyford, Dublin.
There was a time when a bank branch, or more usually several competing branches, were a seemingly permanent fixture on every Irish main street and in every shopping centre. Not any more. Since the Celtic Tiger died almost a decade ago several banks have disappeared altogether while even the survivors have drastically pruned their branch networks.