Two recent supereruptions (magnitude (M) scale ≥ 8), the Young Toba Tuff (YTT), Sumatra, and the Los Chocoyos (LCY), Guatemala, are found to be statistically synchronous at ca. 74 ka and near antipodal. Such planetwide synchroneity of supereruptions is shown to be statistically non-random implying a causal link. We propose that the seismic energy release from the YTT supereruption may have initiated eruption from the contemporaneous “perched” LCY magma system. This near-equatorial supereruption “double-whammy” may be the more compelling source of the significant environmental impacts often attributed to a singular YTT eruption.