Gondwanan sedimentary deposits preserve a rich archive of Triassic non-marine vertebrate evolution. This fossil record is integral to understanding early Mesozoic global change events, including the end-Permian and end-Triassic mass extinctions, Carnian Pluvial Episode, and macroevolutionary events such as the origin of dinosaurs. Until very recently, almost all of these fossil assemblages were dated by exclusively biostratigraphic means, which made robust correlation to the GSSP-defined timescale difficult. Furthermore, recent advances in radioisotopic dating and magnetostratigraphy have demonstrated that many of these biostratigraphic schemes were imprecise and that key index taxa have different first and last appearances across geographic space. Thankfully, over the past ten years, new radioisotopic and magnetostratigraphic age constraints from fossiliferous sequences in South America have allowed the revision of the absolute ages and relative correlation of key Gondwanan vertebrate assemblages. Here, we review these geochronologic age constraints from South America, describe and revise their accuracy and uncertainties, present new U–Pb zircon age data for a key section in Venezuela, infer preliminary age models for these successions, and discuss what they mean for the correlation of fossiliferous Triassic units in Gondwana. This synthesis suggests that although radioisotopic age data are often numerous, the geological uncertainties associated with U–Pb zircon dates using micro-beam techniques (LA-ICPMS and SIMS) mean that the age of most sedimentary units cannot be constrained better than a precision of ± 3–5 Ma. Although CA-TIMS U–Pb zircon ages and 40Ar/39Ar ages can be more precise and accurate, they only result in well-constrained age models when multiple ages are available throughout the section (e.g., Ischigualasto-Villa Unión Basin of northwest Argentina), and even then, issues with lateral correlation within basins remain. Nonetheless, these data demonstrate that South America has high potential for developing a precise and accurate Triassic non-marine numerical timescale for Gondwanan vertebrate evolution.Fil: Irmis, Randall Benjamin. University of Utah; Estados UnidosFil: Mundil, Roland. Berkeley Geochronology Center; Estados UnidosFil: Mancuso, Adriana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Carrillo Briceño, Jorge D.. Universitat Zurich. Instituto Palaontologisches Institut And Museum; SuizaFil: Ottone, Eduardo Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; ArgentinaFil: Marsicano, Claudia Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber"; Argentina