The science fiction thriller, which stars Justin Timberlake and Amanda Seyfried, made more than $2 million in ticket sales, knocking horror Paranormal Activity 3 down to second spot after its reign last week.
Owen Wilson and Rachel McAdams jump up from fourth to third spot with Midnight in Paris, while Contagion drops down two places after making $992,518 at the box office. New entry Warrior made $706,429 and ends up in fifth place.
Other films featured in the top ten included Hugh Jackman's Real Steel and The Three Musketeers in 3D.
The box office top ten in full (figures in Australian dollars):
1. (-) In Time - 2,388,571
2. (1) Paranormal Activity 3 - $1,812,135
3. (4) Midnight in Paris - $1,063,978
4. (2) Contagion - $992,518
5. (-) Warrior - 706,429
6. (3) Real Steel - $704,912
7. (5) The Three Musketeers 3D - $594,534
8. (-) Drive - 466,384
9. (6) Crazy, Stupid, Love - $420,599
10. (7) The Cup - $325,034
Watch Justin Timberlake discuss In Time with Digital Spy below: