Millar attended Gore High School and Otago Boys' High School and moved to Dunedin in 2019.
Millar was signed by Otago for the 2021 Bunnings NPC season and made his debut on 31 October in a non-competition match scoring 21 points in a 33–28 win against Wellington.
On 5 November he made his NPC debut in a 27–25 loss away to Waikato.
In 2021 Millar played for the Highlanders under-20 team
S.C April 2023
Career
 |
Otago Fullback |
2021 - present |
 |
Highlanders Fly Half |
2022 - present |
