These data are from the analysis of cuticular and Dufour’s gland chemistry across alternative social phenotypes within a population of facultatively eusocial Megalopta genalis bees (tribe Augochlorini, family Halictidae). Reproductive bees (queens and solitary reproductives) have distinct glandular and cuticular chemical phenotypes compared with non-reproductive workers. On the cuticle, a likely site of signal transmission, reproductives are enriched for certain alkenes, most linear alkanes, and heavily enriched for all methyl-branched alkanes; these compound classes have known functions as fertility signals among other eusocial insect taxa. Some macrocyclic lactones, compounds that function as queen pheromones in the other eusocial halictid tribe (Halictini), are also enriched among reproductives relative to workers. The intra-population facultative eusociality of M. genalis permits direct comparisons between individuals expressing alternative reproductive phenotypes – females that reproduce alone (solitary reproductives) and social queens – to highlight traits in the latter that are potentially important for eusocial organization. Compared with solitary reproductives, the cuticular chemistries of queens are more strongly differentiated from those of workers and are especially enriched for methyl-branched alkanes. Determining the pheromonal function(s) and information content of the candidate signaling compounds identified will aid in illuminating the early evolutionary history of queen pheromones, chemical signals central to the organization of insect eusociality.