The bank says the process will get underway in September.
One midlands branch is among the 15 being closed by AIB.
The bank has announced it's merging the services with other locations.
The branch in Golden Island Shopping Centre in Athlone is among those being shut, with accounts to be transferred to the main Athlone branch.
AIB says the process will get underway in September and should be complete by December.
The bank says it's made the decision to close the 15 locations due to declining branch visits.
Finance Minister Pachal Donohoe says it is a worrying time for the banking industry: