Chromosome numbers were determined from microsporocytes (meiotic counts) and root-tip cells (mitotic counts) in 201 collections of 51 genera and 119 specific and infraspecific taxa belonging to nine tribes of Asteraceae and Acicarpha spathulata R. Br. of Calyceraceae from Australia, Bolivia, Brazil, Chile, Mexico, and the United States. These include the first reports and new numbers for the basal members of the Barnadesieae and Mutisieae. First reports are provided for 45 taxa, including five genera, Dasyphyllum HBK (2n = 54), Dithyrostegia A. Gray (2n = 14), Epitriche Turcz. (2n = 10), Revealia R. M. King & H. Rob. (2n = 22), and Stifftia J. C. Mikan (2n = 54). In addition, new chromosome numbers are established at the generic level in the genera Barnadesia Mutis (2n = 54), Eremanthus Less. (2n = 34, 30), Macvaughiella R. M. King & H. Rob. (2n = 24), and Trichocline Cass. (2n = 38), and in 12 additional species. Remaining counts augment and agree with previously reported determinations. The base chromosome numbers of Calyceraceae and Asteraceae are discussed in published records and our original counts.