The Irish Open will return to Northern Ireland in 2021 when Portstewart hosts the European Tour event for the second time in four years.
The news was announced at the club's AGM on Thursday evening.
Portstewart's members were told that discussions between the European Tour and the club resulted in an agreement being finalised last week.
The Irish Open returned to Northern Ireland after a 59-year gap when it was played at Royal Portrush in 2012.
The event proved to be a huge success as it attracted a then record attendance for a European Tour event.