| Title | Weekend | Week | Total | % Change | Total Weeks |
| 1 (new) |  | Finding Nemo (2003) | £7,743,638 | £7,743,638 | £7,743,638 | new | 1 |
| 2 (1) |  | Bad Boys II (2003) | £1,488,626 | £2,729,407 | £5,904,665 | -53% | 2 |
| 3 (new) |  | Cabin Fever (2003) | £1,056,338 | £1,056,338 | £1,056,338 | new | 1 |
| 4 (2) |  | Calendar Girls (2003) | £979,974 | £2,212,981 | £14,864,498 | -31% | 5 |
| 5 (3) |  | The Italian Job (2003) | £567,828 | £902,156 | £7,057,938 | -43% | 4 |
| 6 (4) |  | Down With Love (2003) | £435,543 | £748,327 | £1,347,374 | -27% | 2 |
| 7 (5) |  | Pirates of the Caribbean: The Curse of the Black Pearl (2003) | £353,494 | £548,362 | £27,284,670 | -41% | 10 |
| 8 (6) |  | Once Upon a Time In Mexico (2003) | £258,450 | £537,311 | £2,364,423 | -51% | 3 |
| 9 (8) |  | Bright Young Things (2003) | £173,761 | £370,454 | £697,747 | -47% | 2 |
| 10 (new) |  | Kill Bill Volume 1 (2003) | £162,857 | £162,857 | £162,857 | new | 1 |
| 11 (7) |  | Underworld (2003) | £155,439 | £362,464 | £4,280,684 | -66% | 4 |
| 12 (12) | | Baghban (2003) | £91,704 | £155,336 | £273,864 | -23% | 2 |
| 13 (re) |  | interMission (2003) | £63,528 | £63,528 | £1,489,203 | RE | 6 |
| 14 (10) |  | Spy Kids 3D: Game Over (2003) | £58,498 | £68,008 | £7,126,166 | -67% | 11 |
| 15 (new) | | Spellbound (2003) | £57,735 | £57,735 | £57,735 | new | 1 |