The Bajan star outperformed JLS's latest effort 'Take A Chance On Me' to bump previous number one 'Read All About It' by Professor Green and Emeli Sandé to four. 'We Found Love' has now been at number one for four of the six weeks since its release.
Ed Sheeran advances one place to reach the Top 5 for the first time with 'Lego House', while Cher Lloyd's 'With Ur Love' heads two in the opposite direction at six.
Elsewhere, David Guetta and Usher team-up 'Without You' advances another three spots to seven, and Pixie Lott sneaks into the Top 10 with new entry 'What Do You Take Me For'.
Charlene Soraia descends the rankings with 'Wherever You Will Go', which is down three to 11, Florence + the Machine soar a mighty 14 places with 'Shake It Out' at 12 and Loick Essien's 'Me Without You' becomes the week's third-highest new entry at 14.
Meanwhile, Kelly Clarkson's 'Mr Know It All' and 'Jar Of Hearts' by Christina Perri drop six and three respectively to 15 and 17, with new entries 'It Will Rain' from Bruno Mars and 'I Need' by Maverick Sabre alternating between at 16 and 18.
The upper half of the Top 40 is completed by The Wanted, who fall eight from 11 with 'Lightning', and Coldplay's 'Paradise', down three to 20.
The Top 10 in full:
1. (2) Rihanna ft. Calvin Harris: 'We Found Love'
2. (-) JLS: 'Take A Chance On Me'
3. (3) Labrinth ft. Tinie Tempah: 'Earthquake'
4. (1) Professor Green ft. Emeli Sandé: 'Read All About It'
5. (6) Ed Sheeran: 'Lego House'
6. (4) Cher Lloyd ft. Mike Posner: 'With Ur Love'
7. (10) David Guetta ft. Usher: 'Without You'
8. (7) LMFAO: 'Sexy And I Know It'
9. (5) Maroon 5 ft. Christina Aguilera: 'Moves Like Jagger'
10. (-) Pixie Lott ft. Pusha T: 'What Do You Take Me For'
Source: Official Charts Company
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