In this paper I investigate one aspect of the relationship between gender and mock politeness, focussing in particular on sarcastic behaviours. Previous research into sarcasm as an academic concept has suggested that it is more likely to be performed by male speakers. In the British forum data analysed here, there was no correlation between performances of mock politeness and gender. However, there was a preference for labelling male mock polite behaviour as sarcastic, suggesting that the correlation is not between the academic concept of sarcasm and the male behaviour, but between the choice of metapragmatic label and gender of person described. The analysis draws on corpus linguistics, supplemented by survey data, to further describe the relationship between the metapragmatic labels sarcastic and bitchy and gender of the performer.