| Baccharis salicina Torr. & A. Gray, 1842 |
| Baccharis sarothroides A. Gray, 1882 |
| Baccharis sarothroides var. pluricephala Jeps., 1925 |
| Baccharis scabridula Brandegee, 1914 |
| Baccharis scandens Less., 1830 |
| Baccharis schiedeana Benth., 1852 |
| Baccharis sergiloides A. Gray, 1859 |
| Baccharis serratifolia Kunth, 1818 |
| Baccharis serrifolia DC., 1836 |
| Baccharis sordescens DC., 1836 |
| Baccharis spathulata S. Schauer, 1847 |
| Baccharis speciosa A. DC., 1836 |
| Baccharis splendens Heering, 1906 |
| Baccharis squamulosa (A. Gray) M.E. Jones, 1933 |
| Baccharis squarrosa Kunth, 1818 |
| Baccharis sulcata DC., 1836 |
| Baccharis supplex G.L. Nesom, 2018 |
| Baccharis texana (Torr. & A. Gray) A. Gray, 1849 |
| Baccharis thesioides Kunth, 1818 |
| Baccharis thomasii Klatt, 1881 |