National Irish Bank says it has begun a programme to reimburse customers following the High Court Inspectors' report earlier this year.
The inspector's report criticised the bank for imposing improper chargers on some customers.
NIB says documents relating to some accounts are missing, but it is automatically repaying customers where the amounts involved are less than €13, regardless of whether documentation is available. It has today written to 47,000 customers to inform them.
NIB says this will complete the review of fees for around 60% of all affected customer accounts.
The bank says the remaining cases are being investigated case by case, adding that work on this phase will take up to 12 months to complete.
NIB has set aside €10.6m to cover the total cost of this programme. It has also set up a help line for customers, 1850-946-865.
