The singer's eponymous record scored the number one spot in the UK Official Albums Chart after selling 57,000 copies in its first week of release.
Harry's lead single 'Sign of the Times', debuted at number one on the Official Singles Chart last month and is currently number six. Furthermore, eight of the 10 songs from his album are now in the Top 100.
While 23-year-old Harry's solo album has received critical acclaim, former bandmate Liam Payne admitted he is not too impressed.
Speaking recently, he said: "Harry's song, um, I heard... I'll be honest with you, it's not my sort of music.
"It's not something I'd listen to, but I think he did a great job of doing what he wanted to do. That's the way I'd put it best, I think.
"I think the funny thing is, [Harry] would say the same thing about me because he doesn't really listen to hip-hop music.
"Whereas it's like my song's more Rack City, and his song is more of a different era to something I'd listen to, I guess."
Meanwhile, Harry has ended his successful week-long residency on 'The Late Late Show' with a hilarious edition of 'Carpool Karaoke'.
The star joined the show's host James Corden in his infamous car to bring the week to a close with a bang.
During the 10 minute sketch, the duo sang 'Sign of the Times' and 'Sweet Creature' and also discussed Harry's bold fashion choices.
After an energetic performance of Outkast's 'Hey Ya!' and a flawless duet of Diana Ross and Lionel Richie's 'Endless Love', James read famous movie lines with Harry, who has also branched into acting following One Direction's split.
The duo recited iconic movie scenes from 'Titanic' and 'Notting Hill' and finished with a singalong to Harry's track 'Kiwi'.