The singer's sophomore release, which debuted on the chart 57 weeks ago, rose two places to pole position after posting a 37% sales increase following her performance and victories at the Brit Awards on Tuesday (February 21).
In getting to the top of the chart, 21 has this week broken through the four million sales barrier. Her 2008 debut album 19, which is up two to seven, has also reached the two million milestone and, since the Brits, a copy of either album has been purchased on average every seven seconds.
Last week's number one Our Version Of Events by Emeli Sandé is pushed down to second place by Adele, while their fellow Brits winner Ed Sheeran climbs from five to three with +.
Former number one Born To Die by Lana Del Rey slips two to four, singles chart champion Gotye is up one to five with Making Mirrors and Coldplay's Mylo Xyloto is up to six from 11 following a post-Brits performance sales boost of 36%.
The Brits effect continues further down the chart, with Florence + The Machine's Ceremonials climbing a massive 14 places to nine and posting a 72% sales increase, as Doo Wops & Hooligans by Bruno Mars rises four to 11 off the back of his own performance.
Twin Atlantic are up four spots to 12 with Free, Band Of Skulls score the week's highest new entry at 14 with Sweet Sour and The Essential collection from the late Whitney Houston climbs 23 to 17 in the wake of her funeral on February 18.
Also gaining from the Brits are Rihanna, whose album Talk That Talk goes up nine to 18, and Blur, whose Best Of collection enters at 22. In between them are Rebecca Ferguson's Heaven, down nine to 19, and Sorry For Party Rocking by LMFAO, a re-entry at 21.
Source: Official Charts Company
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Watch the Brits performance of 'Rolling In The Deep' from Adele's number one album 21 below:
View the latest Official Top 100 Album Chart