[3H]alpha-Factor and Lucifer yellow were used to measure receptor mediated and fluid-phase endocytosis in the yeast Saccharomyces cerevisiae, arrested in mitosis by depolymerization of the microtubules or due to a mutation preventing nuclear division (cdc16). Both processes continued at roughly the same level as during interphase. This shows that in yeast endocytosis is not interrupted during mitosis like in mammalian cells.