The butterfly species of Tobago have been recorded for over a century, but there has been no assessment of the relative abundance of species and the variation in species richness across the island. This study is a first step towards butterfly community ecology in Tobago, using timed walks and counts. Overall, 79 species comprised of over 2,000 individuals were recorded from 40 hours of sampling across two years, during the transition from rainy to dry season. The species total represented about half of the known total number of species, indicating the value of this methodology for rapid sampling of the island's butterflies. Cluster analysis was used to identify four different assemblages and their constant species. Rarefaction analysis revealed a significant difference in species richness between forest, north coast, and south coast. The highest richness was associated with trails near dry forest in the south-east. Lowland rainforest in the north had a distinctive fauna but low species richness. Significant change across the island is associated with large variation in climatic conditions. This study is important for understanding the biogeographic relationship with Trinidad, the Lesser Antilles, and the continent. The disparity between the forest fauna of Trinidad and that of Tobago is highlighted, along with the absence of key groups in the Lesser Antilles and the highly fragmented nature of dry forest from south-east Tobago via north-west Trinidad to Venezuela.