The board's director James Ferman said the "unusual and disturbing film" was neither illegal nor harmful. One of the characters in the film is disabled from a car crash. But the BBFC said it had showed the film to a top lawyer, a forensic psychologist and an audience of disabled people before granting it an 18 certificate.
David Cronenberg's adaptation of the novel by JG Ballard was the subject of a newspaper campaign to have it banned after its screening at the London Film Festival last year. Westminster Council, in London, gave it an interim ban. Until that is lifted, the number of cinemas at which Crash can be shown in London may be affected.
The film, starring the Oscar winner Holly Hunter, demands a strong stomach. But its opponents ignored the fact that its deliberately sterile atmosphere and the stress on the unfulfilled nature of the characters' relationships acted against it glamourising its subject matter.
The psychologist consulted by the BBFC said there was no sexual deviancy in the film, and that a notorious scene with a woman in callipers was not fetishistic because she was seen as attractive in spite of her scars and limb supports, not because of them.
The BBFC said disabled people shown the film believed the depiction of the woman struggling in callipers mirrored the difficulties that many of them had had to overcome.
Celebrities including Jeremy Irons, Nicolas Roeg, Michael Palin, Ken Loach and film producer Duncan Kenworthy had rallied to the film's defence. A spokesman for Columbia TriStar, the film's UK distributors, said: "We are thrilled the BBFC have finally given Crash the certificate it has always deserved."