The word "fuck" and its variations are used 313 times.
The film sparked a censorship debate in the UK regarding the amount of bad language used. Under current British Board of Film Classification rules, multiple uses of the word "fuck" usually only warrant a 15-certificate, but even a single aggressive use of the word "cunt" tends to lead to an 18-certificate, as was the case with Sweet Sixteen. It was argued, however, that this would prevent the people who could most closely identify with the characters in the film from going to see it, and that such language was much more commonly used, and therefore less offensive, in the north of the UK, where the film was set. The London based censors, however, stuck to their guns, although the local authority who cover the area where the film was shot, Inverclyde, utilized their cinema licensing powers to overrule this, and awarded the film a 15-certificate for screenings in their area.