Auckland Grammar School’s Premier Basketball Team has been ranked in the top ten at the National Secondary Schools Tournament for the last ten years consecutively. In 2025, the team came fourth in the Auckland Championship and at the National Tournament.

NZ age-group representative coaches Dave Mackay, Angela Perrott-Hunt and Lindsay Tait are responsible for coaching the Premier Team and for strengthening the basketball base by developing the skills of junior players. In 2025, the Junior Basketball Team won the Auckland Championship, the Greater Auckland Championship and the Tauranga Tournament. The Under 17A Basketball Team came first in the Auckland Tournament and won the Greater Auckland Champs for the third year in a row.

Teams compete in the Auckland Secondary Schools competition administered by College Sport, at Premier, Open A, Under 17 and Junior levels. In 2026, a new junior competition will run with St Peter’s College.

There is also an intra-school competition for social basketball players. There are no trials and no practices for the Social Basketball League. Students create their own teams and register online to enter. The Social Basketball League is on Friday after school.