MacKillop College enjoys a strong and close school relationship with St Stanislaus' College and the four Bathurst Catholic Primary Schools; The Assumption School, The Cathedral School, Holy Family School and St Philomena’s School. MacKillop equally enjoys a close bond with St Joseph's Primary School at Blayney and St Joseph's Primary School at Oberon.

The girls gather together several times a year with St Stanislaus' College for combined Masses or Liturgies. These occasions recognise our common Christian heritage and allow us to celebrate and witness our faith as a community. Student representatives from each school accept the roles of readers, commentators, liturgical singers and musicians, Eucharistic Ministers and Altar Servers at these Masses. These events additionally allow for social interactions between the schools, with a meal frequently being shared afterwards. Students from both schools look forward to these gatherings in which they can pray, reflect and socialise together. 

Students from MacKillop College and St Stanislaus' College also work together in their leadership of the Catholic Primary School Retreats. These retreats are conducted to help our Catholic Primary School peers prepare for their Sacraments. Prior to Year 3 students undertaking Reconciliation, Year 4 students undertaking First Eucharist and Year 6 students undertaking Confirmation, students in Years 9 and 10 from both MacKillop College and St Stanislaus' College accompany these young people through a retreat day as a way of preparing more thoroughly for these Sacraments. There is also a Leadership Retreat for Year 5 students before they enter their final year of Primary School. The Student Leaders use games, drama activities, reflection and direct instruction to teach the students and also discover a great deal about their own leadership along the way. These retreats establish valuable bonds between the student leaders but also, more importantly, creating lasting connections with the younger students who share our Catholic faith.