The 22-year-old starlet has therefore managed to achieve the second chart double of her career, having also taken 'What's My Name?' to number one on the singles chart this week. She last topped both rankings in 2007 with her third album Good Girl Gone Bad and its lead track 'Umbrella'.
Loud, which has sold 890,000 copies since its release in November, denied Plan B the chance to return to the top spot with The Defamation Of Strickland Banks, which had been leading the race for number one in the midweek chart update.
Meanwhile, Cee Lo Green and Rumer both make a triumphant return to the top ten, as The Lady Killer fires nine places up the chart to four and Seasons Of My Soul smashes its way to six from last week's 15.
Also scaling the charts this week are Eliza Doolittle's self-titled album, which is up 14 to 11, Alfie Boe's Bring Him Home, at 15 from 24, and Adele's 2008 record 19, which climbs to 20 from 32 in its 95th week of release.
The top ten in full:
1. (1) Rihanna: 'Loud'
2. (3) Plan B: 'The Defamation Of Strickland Banks'
3. (2) Take That: 'Progress'
4. (13) Cee Lo Green: 'The Lady Killer'
5. (6) Mumford & Sons: 'Sigh No More'
6. (21) Rumer: 'Seasons Of My Soul'
7. (4) Tinie Tempah: 'Disc-Overy'
8. (9) Ellie Goulding: 'Lights'
9. (8) Katy Perry: 'Teenage Dream'
10. (7) Kings Of Leon: 'Come Around Sundown'
Source: Official Charts Company
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