The live-action/animation hybrid, co-starring James Marsden and Kaley Cuoco, takes in £1.39 million to secure first place. Jake Gyllenhaal's science fiction thriller Source Code runs Hop close at the chart summit, opening with £1.3 million.
Last week's number one Limitless is at number three ahead of Sucker Punch, which bows at a disappointing number four on the back of unfortunate reviews.
The Eagle is at number five, while A Turtle's Tale: Sammy's Adventure is the biggest faller as it tumbles down four spots to number six.
Elsewhere, Rango continues its impressive box office run. The Johnny Depp animation has been in cinemas for a month and grossed £6.3 million in total from UK screens.
The UK box office top ten in full:
1. (-) Hop - £1,392,740
2. (-) Source Code - £1,306,661
3. (1) Limitless - £1,206,219
4. (-) Sucker Punch - £814,976
5. (3) The Eagle - £472,357
6. (2) A Turtle's Tale: Sammy's Adventure - £365,258
7. (4) Rango - £289,021
8. (5) Unknown - £276,657
9. (7) Anuvahood - £219,688
10. (9) The Lincoln Lawyer - £146,962
Watch the trailer for Hop below: