The study draws on a diverse sample of adult users of online support groups to investigate how men and women engage in written conversations, and how these interactions are carried out in English and in Spanish contrastively. We will see to what extent female and male communicators in online support groups display similar power behaviours since some authors believe that these fora seem to provide a context where factors such as power and status are neutralised. In general, the detailed quantitative analysis suggests that women use powerless markers far more frequently than men. Therefore the findings support the contention that gender-based differences persist on the Internet, an arena which was initially believed to be free of built-in bias. On the other hand, the inter- and cross-cultural comparison indicates that the discourse practices in English include more powerless markers than those in Spanish. Interestingly, the abundant use of occurrences of formal addresses and polite forms displayed by men in Spanish may suggest that, in online support groups, men may be adopting communicative strategies traditionally associated with women’s discourse.