St Peter's is an Anglican school, with the Bishop of Johannesburg as its Visitor.

Attendance at assembly is compulsory for staff and pupils. At the start and end of each term, a Eucharist is celebrated for all pupils from Grade 4 to 7. In all school services, Grade 7 pupils are selected for Serving duties.

On their own initiative, girls from Grade 3 upwards may be admitted to Holy Communion.

While Christian values are woven into all aspects of daily life at the school, an understanding of other religions is fostered. Pupils of all religions are accepted into the school, with specific religious days and festivals of other cultures recognised in assembly and class lessons.