The affected staff will receive 7.25 weeks pay for each year of service to the bank.
Late last year PTSB offered staff paid career breaks in an effort to cut costs.
Today's announcement that it is closing 11 branches follows the closure of its network of 48 'tied agents' earlier this year.
In a statement his afternoon the UNITE trade union said that its members had agreed to incentivised career breaks, comprehensive redeployment and an effective recruitment embargo.
The statement said: 'We do feel let down and disappointed at this requirement to close branches with consequent redundancy, and inevitable disruption and redeployment for those members remaining with the organisation'.
