The X Factor star's latest release beat fellow new entry 'Feel So Close' by Calvin Harris to pole position, following in the footsteps of his August 2010 debut 'Please Don't Let Me Go'.
Murs celebrated on Twitter after the result, writing: "NUMBER 1!! Wooooooooooo woooo!! Thanks to everyone who downloaded it!! X I'm soooo happy!! Its PUCKA!!! X"
Last week's number one Wretch 32 is instead forced to settle for fourth with 'Don't Go', while album chart champion Will Young achieves his tenth Top 10 hit with 'Jealousy', a new entry at five.
Emeli Sandé's 'Heaven' falls from the runner-up spot to seven, Rizzle Kicks - who lend their vocals to Murs's chart-topper - are a non-mover at eight with 'Down With The Trumpets', while 'The A Team' by Ed Sheeran and David Guetta's 'Little Bad Girl' fall three apiece to nine and ten.
Outside the top-sellers, Bruno Mars scrambles seven more spots up the rankings to 11 with 'Marry You', Nero drop from five to 13 with 'Promises' and JLS tumble five positions with their Dev team-up 'She Makes Me Wanna' at 14.
Noel Gallagher's High Flying Birds debut at 15 with 'The Death Of You And Me', while Jessie J's latest single 'Who's Laughing Now' continues to advance, finishing at 16 from last week's 21.
Sean Kingston returns to the chart at 18 with his seventh UK single 'Party All Night (Sleep All Day)', as Cher Lloyd's 'Swagger Jagger', Beyoncé's 'Best Thing I Never Had' and 'Louder' by DJ Fresh fall eight together to complete this week's Top 20.
The Top 10 in full:
1. (-) Olly Murs ft. Rizzle Kicks: 'Heart Skips A Beat'
2. (-) Calvin Harris: 'Feel So Close'
3. (3) Maroon 5 ft. Christina Aguilera: 'Moves Like Jagger'
4. (1) Wretch 32 ft. Josh Kumra: 'Don't Go'
5. (-) Will Young: 'Jealousy'
6. (4) Christina Perri: 'Jar Of Hearts'
7. (2) Emeli Sandé: 'Heaven'
8. (8) Rizzle Kicks: 'Down With The Trumpets'
9. (6) Ed Sheeran: 'The A-Team'
10. (7) David Guetta ft. Taio Cruz & Ludacris: 'Little Bad Girl'
Source: Official Charts Company
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