Absa CE Nallie Bosman told Sake the group had already closed 450 branches between April 1998 and March of this year.
Last year, the group closed 100 branches.
In 1992, when United, Trust Bank, Volkskas and Allied amalgamated, Absa had 44 000 employees. This figure is now 34 000. Bosman said only 2 500 of these 10 000 workers were retrenched.
Bosman said he did not expect many workers would lose their jobs because of the closure of the 50 branches.
He said employees in urban areas could easily be transferred to other branches, and in small towns, staff are transferred to a neighbouring town.
Arrangements would also be made to accommodate customers.
Bosman said apart from the overlapping of branches in certain parts, business areas in cities were moving, which meant service points had to change to remain profitable.
"It is not that we are only closing branches - we are opening new ones too. In Douglas, a relatively small town in the Northern Cape, another branch has been opened, because there was a demand for it," he said.
About 55% of the bank's customer base is black, and the group has committed itself to pushing its current 33% of black employees up to 50% within the next five years.
Absa's share price on the Johannesburg Securities Exchange closed 45c weaker at R34.35 on Friday afternoon.