AIB-owned First Trust Bank is re-branding under its parent company's name.
First Trust Bank, which trades in Northern Ireland, is a wholly-owned subsidiary of Allied Irish Banks.
The name-change will mean that all First Trust Bank operations, products and services will re-brand as AIB on a phased basis from 2020.
The company has said this is to "create a shared and unified brand for our customers across all our business operations".
Over the past number of years, AIB Group has invested €11.5m (stg£10m) in transforming First Trust Bank.
The re-branding marks a continuation of the bank's strategy of closer integration in its three main markets.
However, First Trust Bank customers will see no interruption of services and will not be required to take any action.
Adrian Moynihan, head of First Trust Bank in Northern Ireland, said: "AIB is very proud of everything First Trust Bank has accomplished since its creation in 1992.
"We are keen to build on our strong and positive presence in Northern Ireland in the future and our decision to re-brand First Trust Bank as AIB reflects this commitment.
"Re-branding as AIB is a natural progression in our transformation given we are AIB in both the Republic of Ireland and Great Britain.
"It reflects our commitment to our presence in Northern Ireland and our desire to provide all our customers with a consistent and exceptional customer experience."
Colin Hunt, CEO of AIB Group, added: "Today we are reinforcing our commitment to Northern Ireland with this investment to re-brand First Trust Bank so it aligns with the overall AIB Group.
"Operating as one brand allows us to enhance our offering to customers across the jurisdictions in which we operate, and unifies us all behind our purpose to back our customers to achieve their dreams and ambitions."