Staff at Bank of Ireland's computer division, ITSIS, have voted in favour of outsourcing the operation to Hewlett Packard.
The result of the controversial Irish Bank Officials' Association (IBOA) ballot was welcomed by the bank this lunchtime. A contract is expected to be signed next month.
The proposal to outsource the operation had initially been opposed by the IBOA, which represents most of the staff employed in the ITSIS division. Under the terms of the contract, staff within the ITSIS division would transfer for a initial seven-year period to the US multinational.
In July, 200 of the union's members held a one-day strike to highlight concerns that the outsourcing would threaten their job security and limit their say in future collective bargaining arrangements.
It is believed that concessions on the issue of job security, along with union recognition, were sufficient to carry this morning's ballot.
Bank of Ireland and Hewlett Packard had already accepted the proposals, which were brokered by the chief executive of the Labour Relations Commission, Mr Kieran Mulvey.
ITSIS staff provide support for ATMs and internet banking among other services.