Primary schools with seven teachers or more will be entitled to appoint an administrative principal from September under a plan drawn up by the outgoing Minister for Education and Science, Mr Martin.
In the existing system only schools with eight teachers or more are entitled to an administrative principal.
Administrative principals are not required to undertake teaching duties, unlike teaching principals, who are assigned to small schools.
Changing the rules for the appointment of administrative principals was recommended by the Working Group on the Role of the Primary School Principal.
Mr Martin also announced that schools with teaching principals who have more than 25 pupils and between two and six teachers will be allowed a substitute cover.