St Paul's is composed of five sub-schools:
In 1857 the site of the school was first settled by British settlers. In 1859, the British colony of Queensland was founded. In 1886 the original wooden building, the Old Farmhouse, was built. It still stands today. On 13 February 1958 the Church of England acquired the property via a bequest from Sir Edwin Tooth for the "establishment of an all boys grammar school". The school opened on 31 January 1961 with a small staff of three and an enrolment of sixty-four boys between grades eight and twelve. Years later the school expanded its clientele and became fully co-educational. This allowed for a substantial increase in funds, which meant much-needed facilities could be built.
St Paul's Campus is located in Bald Hills, approximately 17 kilometres (11 mi) north of the Brisbane Central Business District. The school is situated on the bank of the South Pine River, on the border between the Brisbane City Council and Moreton Bay Regional Council. The area surrounding the school is a mix of residential and rural properties.
The School occupies a single 51 hectare campus, which includes both the school's buildings as well as its sporting fields and grazing land. A pair of hoop pines which were originally planted in the 1850s are now heritage-listed.
Many of the buildings on the school campus are 40 years old. More modern facilities include the School Chapel, the Music Centre, the Middle School, the renovated Design/Technology building, the Geize Library and new Science Laboratories. Construction was recently completed on the new Sutton Building, replacing the old building of the same name at the beginning of 2012. It includes the school's first café – Sippers@Suttons as well as English classrooms and the international school.