Published Thursday, 03 January 2013
A general view of the Ulster bank headquarters in Belfast. (© PA)
The bank said the closure plan comes after a review of the branch network to ensure that they "are operating in the correct locations for our customers".
It comes after staff were told that 950 jobs were set to go in January last year.
"We will be closing in the region of 20 branches and sub offices on the island of Ireland in 2013," Ulster Bank said in a statement on Thursday.
"We expect to be in a position to provide further details in the next few weeks and will communicate directly with our customers and employees at that time."
Last year Ulster Bank revealed it paid out over £18m to almost 300,000 Northern Irish customers after a technical glitch left them without proper access to their bank accounts for weeks over the summer.
The staff redundancy programme was put hold while the bank dealt with the crisis.
There are 90 Ulster Bank branches in Northern Ireland and 146 in the Republic of Ireland.