| Title | Weekend | Week | Total | % Change | Total Weeks |
| 1 (new) |  | Rocknrolla (2008) | £1,565,439 | £1,565,439 | £1,565,439 | new | 1 |
| 2 (2) |  | Mamma Mia! () | £1,431,775 | £3,146,203 | £57,687,650 | -8% | 9 |
| 3 (new) |  | The Duchess () | £1,402,200 | £1,402,200 | £1,402,200 | new | 1 |
| 4 (1) |  | Step Brother's () | £1,105,342 | £2,321,782 | £4,003,274 | -34% | 2 |
| 5 (new) |  | Disaster Movie (2008) | £925,655 | £925,655 | £925,655 | new | 1 |
| 6 (3) |  | The Strangers (2008) | £746,507 | £1,598,429 | £2,849,053 | -40% | 2 |
| 7 (5) |  | The Dark Knight () | £586,944 | £630,913 | £46,418,476 | -35% | 7 |
| 8 (4) |  | Hellboy II: The Golden Army () | £507,908 | £1,126,555 | £6,772,936 | -50% | 3 |
| 9 (6) |  | Get Smart () | £350,456 | £863,385 | £4,356,991 | -51% | 3 |
| 10 (new) |  | Bangkok Dangerous () | £307,420 | £307,420 | £307,420 | new | 1 |
| 11 (10) |  | WALL•E () | £277,277 | £551,004 | £22,034,562 | -23% | 8 |
| 12 (9) |  | Wild Child () | £203,776 | £513,113 | £4,710,679 | -48% | 4 |
| 13 (7) |  | Babylon A.D. (2008) | £161,179 | £480,920 | £1,017,888 | -70% | 2 |
| 14 (8) |  | You Don't Mess With the Zohan (2008) | £139,677 | £431,427 | £5,200,666 | -67% | 4 |
| 15 (12) |  | Star Wars: The Clone Wars () | £131,252 | £256,524 | £2,775,350 | -37% | 4 |