The Irish Bank Officials' Association has served notice on Bank of Ireland of a one-day strike at the bank's information technology subsidiary.
The action is planned for the 23 July.
The dispute is over plans to transfer the bank's IT services to the multinational company, Hewlett Packard.
The IBOA says 300 staff fear for the future of their jobs.
However, IBOA General Secretary Larry Broderick stressed that the main Bank of Ireland operation would not be affected.
Bank of Ireland holds its annual general meeting later today.
