Discourse particles are among the most commented-upon features of Colloquial Singapore English (CSE). Their use has been shown to vary depending on formality, context, gender and ethnicity, although results differ from one study to another. This study uses the Corpus of Singapore English Messages (CoSEM), a large-scale corpus of texts composed by Singaporeans and sent using electronic messaging services, to investigate gender and ethnic factors as predictors of particle use. The results suggest a strong gender effect as well as several particle-specific ethnic effects. More generally, our study underlines the special nature of the grammatical class of discourse particles in CSE, which is open to new additions as the sociolinguistic and pragmatic need for them develops.