The 20th Century Fox animated sequel, which opened wide across UK cinemas over the weekend, pulls in more than £10 million to knock last week's chart-topper The Amazing Spider-Man into second place.
Ice Age secured the number one spot two weeks ago thanks to an early release in Scotland, Wales, Ireland and previews in the UK.
Channing Tatum's male stripper movie Magic Mike is a new entry at number three, with Seeking a Friend for the End of the World and Bollywood release Cocktail completing the top five.
The biggest chart faller is Katy Perry: Part of Me, which drops five places to number nine after experiencing a 64% dip in ticket sales.
The UK box office top ten in full:
1. (2) Ice Age 4: Continental Drift - £10,087,052
2. (1) The Amazing Spider-Man - £3,905,474
3. (-) Magic Mike - £2,651,015
4. (-) Seeking a Friend for the End of the World - £357,200
5. (-) Cocktail - £296,778
6. (3) The Five-Year Engagement - £258,618
7. (5) Men in Black 3 - £215,720
8. (6) Prometheus - £185,853
9. (4) Katy Perry: Part of Me - £161,114
10. (7) Snow White and the Huntsman - £152,741
Watch a Dark Knight Rises-spoofing trailer for Ice Age 4 below: