Nicaragua is a biodiverse country, but documented herpetological specimens are underrepresented compared to neighboring countries. In 2018 we conducted a collaborative expedition between the University of Michigan Museum of Zoology and Nicaraguan biologists. We visited sites in the Pacific Low‑ lands, Caribbean Lowlands, and the Central Highlands, representing the three major biogeographic regions of Nicaragua. We collected specimens of 100 species from a total of 106 encountered. We provide acces‑ sion numbers and morphological, genetic, and ecological information for these specimens. We recorded 23 new departmental records and the first country record of Metlapilcoatlus indomitus (Smith & Ferrari‑Castro, 2008), filling gaps in the known distribution of the species within Nicaragua and across Central America. When available for each species, we provide range maps and comparative genetic trees including conspecific reference sequences from the region, making this work a significant addition to existing checklists of the herpetofauna in Nicaragua.