This article presents the results of the first diachronic study of obsidian procurement patterns in the Gulf of Fonseca on the Pacific coast of Central America; it sheds light on the integration of the region in long-distance exchange systems. This study is based on portable X-ray fluorescence spectroscopy (pXRF) analysis of all 713 obsidian artifacts collected from Terminal Classic and Postclassic contexts on Tigre Island, Honduras, and of 54 additional obsidian artifacts from two sites on the south coast of Honduras that are housed in museum collections. Analysis of obsidian artifacts collected in the excavation of the earlier occupation of the site of La Tigüilotada (AD 800–1200) on Tigre Island revealed the predominance of Ixtepeque obsidian and the lesser presence of Güinope obsidian. Obsidian artifacts from excavations of the reoccupation of La Tigüilotada (AD 1300–1500) and of the site of Gualorita (AD 1400–1550) relied almost exclusively on La Esperanza obsidian. Least-cost path analysis shows likely riverine routes connecting all three sources to the Gulf. We contextualize these results within prior obsidian sourcing studies from the region and conclude that precolonial island settlements took part in different transference networks from their mainland counterparts.