Whanganui Girls' College will be led by Deputy-Principal Nita Pond next term.
A statement from the school last month said former Principal Sharon Steer had resigned for "personal and family reasons" and returned to Auckland, with fellow Deputy-Principal Craig Ritani taking over for the remainder of term two.
The search is now on for someone to fill Steer's role, with a new appointment expected to start in term four.
Steer was principal for just over two years, taking over from Tania King, who was in charge from 2014 to 2019.
Girls' College's triennial election for its Board of Trustees will be held in term three.