The St Matthew's competition, held in the second to last week of term, was dominated by Grey House, which won Best House overall, Best Song, Best Student Accompaniment and Best Hymn, with house member Lauren Tonkin winning the prize for Best Student Arrangement.
Cobham House Leader Makaylah Julian won the award for Best Conductor.
St Matthew's principal Kiri Gill said the House Music Competition was always a magical night that celebrated success and diversity. "Every girl at school takes part in the House Music and it fosters such a wonderful house and school spirit by giving the senior students responsibility for organising and teaching the younger girls," she said.
"It also gives all of our girls the opportunity to experience what it's like to perform for a big crowd, and every year the bar is raised as they strive to be more creative and more brilliant than the year before."
Ms Gill said the musical competition was a highlight of the school year for staff and parents.
"It's always such a delight to witness the exuberance of our girls, and audience first-timers are often overwhelmed by how professional it is."
Rathkeale's competition, held on the last Friday of term, was "similarly spectacular", Ms Finnigan said.
Halberg House won Best House overall, Best Hymn and Best Song. Blake won Best Small Group and Best Accompanying Group and their House Leader Sam Kyle won Best Conductor.
Rathkeale principal Willie Kersten said the House Music tradition was "a wonderful way of giving every boy a chance to experience what it's like to perform".
"I always love to see boys who aren't necessarily born performers or our star musicians and singers taking the chance to step out of their comfort zone and have a go.
"Their contribution to the team effort is amazing," Mr Kersten said.