The X Factor winners went straight to the top with their first proper single since their cover of Damien Rice's 'Cannonball' last Christmas.
The girl group sold over 107,000 copies over the past week, and knocked last week's chart-toppers Sam and the Womp down to second place with 'Bom Bom'.
"Wooh! Number 1! We want to thank all the Little Mixers who went out and bought the single," the band said. "You've made all our dreams come true.
"It means a lot because obviously we got a number one at Christmas with 'Cannonball', but that wasn't our song really, so now that we've become number one with our own song that we wrote, we're so proud, best feeling ever. Continue to listen to it and dance away in your bedrooms in your pants!"
Rita Ora dropped one place to three with 'How We Do (Party)', while Public Enemy climb seven spots to four with 'Harder Than You Think', the track used for Channel 4's Paralympic coverage.
Owl City and Carly Rae Jepsen leap 12 places to five with 'Good Time', ensuring that both will not be labelled one-hit-wonders after 'Fireflies' and 'Call Me Maybe'.
Wiley drops three to six with former number one 'Heatwave', with Florence + the Machine falling one to seven with 'Spectrum'.
Taylor Swift falls three to eight with 'We Are Never Ever Getting Back Together'. Emeli Sandé drops five to nine with 'Read All About It Part III', while Angel falls one with 'Wonderful' to complete the Top 10.
X Factor contestant Lucy Spraggan lands at 11 with 'Last Night', despite her track being deleted from iTunes midweek.
Of Monsters and Men climb a further nine places to 12 with 'Little Talks', while Fun. climb ten spots to 14 with 'Some Nights'.
Former N-Dubz member Fazer's debut solo single 'Killer' is a new entry at 17, while Cover Drive enter at 29 with 'Explode'.
Watch the video for Little Mix's 'Wings' below:
Source: Official Charts Company
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