||Increasing evidence suggests that key fitness-related behaviours of animals related to courtship and mating may be disrupted by anthropogenic stressors, including artificial light at night (i.e. light produced from anthropogenic sources). Despite its ubiquity in urban habitats, we currently know very little about how artificial night lighting affects the reproductive behaviours of most animals. Our study examined the effects of chronic (lifetime) exposure to one of four ecologically relevant intensities of artificial light at night (0, 1, 10 or 100 lx at night) on courtship and mating behaviours and acoustic sexual signalling in a common nocturnal and crepuscular insect, the Australian black field cricket, Teleogryllus commodus. We found that lifetime exposure to brighter (10â100 lx) artificial light at night affected some aspects of courtship and mating behaviour: it influenced mate choice and mating efficiency in a sex-specific manner, but did not affect the multivariate structure of male courtship calls. Our results suggest that chronic exposure to bright light at night may affect some aspects of mate choice and reproductive behaviour in this common insect, and warrants further study across taxa.