This is the fourth time that the band have made it to No.1, first achieving the feat 28 years ago with The Number Of The Beast.
Final Frontier's arrival means that Eminem's Recovery returns to the runner-up spot after recapturing pole position on the chart last week. One place behind is The Saturdays, who notch up their highest UK album chart position to date with this week's second-highest new entry, Headlines.
Elsewhere in the top 10, Eliza Doolittle's self-titled album and Lady GaGa's The Fame Monster each drop down four spots to eight and nine respectively, just ahead of another new entry, The Illusion Of Safety by The Hoosiers.
Meanwhile, all but one of the positions between 11 and 20 are occupied by a faller, the lone exception being David Gray's Foundling, which debuts at 18.
The top 10 in full:
1. (-) Iron Maiden: 'Final Frontier'
2. (1) Eminem: 'Recovery'
3. (-) The Saturdays: 'Headlines'
4. (3) Plan B: 'The Defamation Of Strickland Banks'
5. (2) Arcade Fire: 'The Suburbs'
6. (6) Michael Bublé: 'Crazy Love'
7. (8) Paolo Nutini: 'Sunny Side Up'
8. (4) Eliza Doolittle: 'Eliza Doolittle'
9. (5) Lady GaGa: 'The Fame Monster'
10. (-) The Hoosiers: 'The Illusion Of Safety'
Source: Official Charts Company
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