According to SoundScan Canada, which measures retail music sales here, Spears' album debuted at the top of the charts, with sales of 95,275.
To put it in perspective, Pearl Jam's much anticipated new album "Binaural" entered the charts just behind Spears, but sold 35,966 copies.
The "Mission:Impossible 2" soundtrack held on to third place with sales of 17,037.
In the U.S., with approximately 10 times the population, "Oops" sold an estimated 1.3 million copies, according to SoundScan.
Spears' Canadian numbers are impressive, but don't come close to the Canadian record for highest debut for a female singer. That title belongs to Celine Dion, who sold 230,000 copies of "Let's Talk About Love" in November 1997.
In the U.S., Jive Records, which represents Spears, Backstreet Boys and *NSync, now holds the distinction of holding the three highest opening-week sales figures in SoundScan's 10 year history: *NSync's "No Strings Attached" sold 2.4 million records in its first week, while the Backstreet Boys' "Millennium" sold 1.13 million copies.
Here's the current top 10 selling albums according to SoundScan Canada: