Chromosome numbers are reported for the first time for 245 individuals of 93 taxa and cultivars and two hybrids from 13 genera from eastern Canada and the eastern United States. Nearly all of the reports are for asters in Symphyotrichum plus Doellingeria, Eurybia, Oclemena, and Sericocarpus, and for goldenrods in Solidago and Euthamia. Corrections or changes in identifications for eight previous reports are also listed. The following are first documented reports for the taxa: Chrysopsis highlandsensis, 2n = 5II from Florida; Solidago simulans, 2n = 36 from North Carolina; Solidago villosicarpa, 2n = 18 from North Carolina; Symphyotrichum fontinale, 2n = 50 from Florida; Symphyotrichum grandiflorum, 2n = 30 from North Carolina; Symphyotrichum parviceps, 2n = 48 from Missouri; and Symphyotrichum rhiannon, 2n = 48 from North Carolina. A number of the counts are first reports for a particular taxon in a state: e.g., Brintonia discoidea, 2n = 18 from Alabama; Doellingeria umbellata var. umbellata, 2n = 18 from Tennessee, Eurybia spectabilis, 2n = 72 from South Carolina; Symphyotrichum oolentangiense, 2n = 32 from Tennessee.