Goodbody Stockbrokers is to outsource its clearing and settlement operations to Pershing, a subsidiary of Bank of New York.
Pershing, which will set up a subsidiary in Dublin, will settle all of Goodbody's client trades and issue contract notes in the firm's name.
Goodbody has over 11,000 investors and is owned by AIB. It is the first Irish stockbroker to outsource such activities.
A spokesman said some of the Goodbody staff involved in the operation would be moved to Pershing, while others would be redeployed within the Goodbody Group. Others would also be redeployed within the greater AIB Group.