The singer, 18 - who's currently spending time at home in Ireland - had the braces on his teeth checked out yesterday and was thrilled to learn that he'll have a perfect smile in a matter of months.
'Been to dentist today ! got them tightened up and stuff! he tells me i will be gettin braces off in 6 months...teeth moving fast ! sick,' he told his Twitter followers.
Though Niall's understandably excited to see the back of his train tracks, some of his fans will be very sad to see them go.
'Nooooo @NiallOfficial keep your braces on forever everyone loves them,' pleaded one.
Another added: '@NiallOfficial is so adorbs with his braces.'
VIDEO: One Direction's Harry Styles supports Cancer Research UK
VIDEO: One Direction coming soon
VIDEO: Teen Now meets One Direction part 1VIDEO: Teen Now meets One Direction part 2
VIDEO: One Direction at Capital FM Jingle Bell Ball part 2