The five-piece band - Liam Payne, Niall Horan, Zayn Malik, Louis Tomlinson and Harry Styles - are said to have shifted more records than Arctic Monkeys, Kasabian, Mumford and Sons and Noel Gallagher's High-Flying Birds combined.
And much of their success can be attributed to their US stardom as well as their popularity in the UK.
The band's debut single What Makes You Beautiful shifted 5m copies across the world, three million of which were sold in the States.
They have also sold 3m copies of their debut album Up All Night and can add a further 1m sales of their DVD Up All Night: The Live Tour to their awesome tally.
The band have since been rewarded with a special disc from Sony Music and Simon Cowell's company Syco in recognition of their success.
Liam Payne said they were 'ecstatic and humbled' by the accolade and added, 'We have an incredible team of people around us who have helped us achieve this.
'Above all we would like to thank our fans. We owe all our success to them.'
The band are reportedly set to release a new single next month, with their second album due out before the end of the year.
