According to Billboard, '21' this week clocked over the one million mark with sales to date of 1.03 million.
She revealed that the inspiration for '21' came from listening to Mumford & Sons 'Sign No More' which co-incidentally is the second biggest album of the year in the USA.
However, sales are indicating a slow sales year. 'Sign No More' has sold 645,000 units to date after being released a year ago.
Adele '21' will reclaim the top spot on the Billboard chart this week with sales of around 8,000 units.
Next week, Foo Fighters 'Wasting Light' will come in at number one on sales over 200,000.