The X Factor winner has been at the top of the pile for three weeks altogether, and has now sold 971,000 copies in just four weeks.
will.i.am and Britney Spears stay at number two with 'Scream & Shout', just 6,000 copies behind Arthur.
Psy is also a non-mover at three with 'Gangnam Style' in its 17th week inside the Top 40, while Bruno Mars climbs two places to four with 'Locked Out of Heaven'. Taylor Swift drops one to five with 'I Knew You Were Trouble'.
Olly Murs and Flo Rida drop two to six with 'Troublemaker' and Rihanna climbs five places to seven with 'Stay'.
Rihanna is also a non-mover at eight with 'Diamonds', with Swedish House Mafia climbing back into the Top 10 at nine with 'Don't You Worry Child'. Labrinth stays at ten with 'Beneath Your Beautiful'.
Calvin Harris and Tinie Tempah re-enter the Top 40 with 'Drinking From the Bottle', climbing 28 places to 15.
Florence & the Machine also rise 16 places with the Calvin Harris-remixed 'Spectrum' at 35, while DJ Fresh climbs 12 places to 22 with 'Gold Dust'.
Carly Rae Jepsen's 'Call Me Maybe' is eight spots to 23 after 41 weeks. Ellie Goulding's 'Anything Could Happen' also re-enters at 36.
Watch the video for James Arthur's 'Impossible' below:
Source: Official Charts Company
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