Born This Way becomes only the 17th album to sell a million in a week since SoundScan began tracking sales data in 1991. It's the highest sales week for an album since 50 Cent's The Massacre in 2005.
Gaga becomes the first artist to top a million sales since Taylor Swift debuted Speak Now with just over a million in November (10), and only the fifth woman to achieve the feat - behind Swift, Britney Spears, Whitney Houston and Norah Jones - but her figure falls well short of 'N Sync's record-breaking 2.4 million sales figure for 2000's No Strings Attached.
Meanwhile, country star Brad Paisley debuts This Is Country Music at two on the new countdown with 153,000 sales, and former chart-topper Adele slips to three with 126,000 sales for the week.
The Glee cast's Glee: The Music, Vol. 6 and compilation MMG Presents: Self Made, Vol. 1 round out the new top five.