The track is the Take That star's first chart-topper since 2004's 'Radio', and becomes his seventh solo number one.
It is his 14th number one overall including tracks with Take That, equalling bandmate Gary Barlow's record. His tally is 16 if including charity records by Band Aid 20 and Helping Haiti.
'Candy' sold 137,000 copies in its first week on sale, becoming the third fastest-selling track of the year so far.
"Number one, yeah! So chuffed, really, really happy that 'Candy' reached the top spot," Williams told The Official Charts Company. "Good work Team Williams, and thanks to everyone who got it there. I'm so excited about this album and this is a great start."
Labrinth and Emeli Sandé fall one place to two with 'Beneath Your Beautiful', but still shifted just under 103,000 copies in its second week on the chart.
Wiley enters at three with 'Can You Hear Me (Ayayaya)', his second top three hit in three months following number one 'Heatwave'.
Swedish House Mafia drop two to four with former number one 'Don't You Worry Child', while Adele climbs back up two to five with 'Skyfall'.
Calvin Harris and Florence Welch drop three to six 'Sweet Nothing', while Psy falls two to seven with 'Gangnam Style'.
Rihanna dips four places to eight with 'Diamonds', with Maroon 5 falling one to nine with 'One More Night'. Taylor Swift also falls one place to complete the Top 10 with 'We Are Never Ever Getting Back Together'.
The Lumineers climb a further 11 places to 12 with 'Hey Ho', following its use on a television advert. Fun. re-enter the chart at 13 with their massive seller 'We Are Young', after they performed it on The X Factor last weekend.
Paloma Faith climbs back up nine places to 20 with her of INXS's 'Never Tear Us Apart' after performing it on Strictly Come Dancing. Fun. also climb 15 spots to 23 with 'Some Nights'.
Calvin Harris and Tinie Tempah score a new entry at 25 with 'Drinking from the Bottle'. Ben Howard lands at 32 with 'Burgh Island'.
Asaf Avidan and the Mojos land at 30 with their massive Europe hit 'One Day/Reckoning Song (Wankelmut Remix)'. Hot Natured and Ali Love also sneak in at 40 with 'Benediction'.
Watch the video for 'Candy' by Robbie Williams below:
Source: Official Charts Company
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