Ubisoft's highly anticipated action title beats FIFA 13 and WWE 13 to the top spot.
Assassin's Creed 3 is the All Formats All Prices UK video game chart No. 1, becoming Ubisoft's biggest ever launch.
The game managed to outsell the publisher's previous record holder, Assassin's Creed: Revelations, by a massive 117,000 units. Assassin's Creed 3 is the second biggest launch of 2012, only being bettered by EA's FIFA 13.
FIFA 13 remains at No. 2, dropping just 2 per cent week on week, while WWE '13 enters at No. 3, Football Manager 2013 debuts at No. 4, and Need for Speed Most Wanted is new at No. 5. Despite a mildly disappointing fifth place for NFS, it did sell 17,000 more units at launch than NFS: The Run managed last year.
Elsewhere in the chart, last week's No. 1, Medal of Honor Warfighter, falls to No. 6 due to a 46 per cent drop off, and Forza Horizon fell by 50 per cent to chart at No. 7. The Top 10 is rounded off by Skylanders Giants, Just Dance 4, and Dishonored.
The only other new entry in the Top 40 is Vita title Assassin's Creed Liberation, which entered at No. 14. Despite its lowly position, the game managed the third biggest debut for a Vita game, only being bettered by Uncharted: Golden Abyss and FIFA Football.
UKIE Games Charts, compiled by GfK Chart-Track, (All Prices) Week 44, 2012
1. ASSASSIN'S CREED 3
2. FIFA 13
3. WWE '13
4. FOOTBALL MANAGER 2013
5. NEED FOR SPEED MOST WANTED
6. MEDAL OF HONOR: WARFIGHTER
7. FORZA HORIZON
8. SKYLANDERS GIANTS
9. JUST DANCE 4
11. PROFESSOR LAYTON AND THE MIRACLE MASK
12. MOSHI MONSTERS: MOSHLINGS THEME PARK
13. RESIDENT EVIL 6
14. ASSASSIN'S CREED LIBERATION
15. POKEMON BLACK VERSION 2
16. THE ELDER SCROLLS V: SKYRIM
17. F1 2012
18. DOOM 3: BFG EDITION
19. BORDERLANDS 2
20. LEGO BATMAN 2: DC SUPER HEROES
Ubisoft must be pleased with the sales of Assassin's Creed 3, but elsewhere performances were mixed. WWE '13 and Football Manager 2013 both sold less than last year's titles managed in week one, while EA might have hoped for better from NFS given its strong reviews.
Next week's chart should be dominated by Halo 4 - if the game fails to topple Assassin's Creed 3 it'll like be considered a huge disappointment by Microsoft.
Source: UKIE Games Charts, compiled by GfK Chart-Track