| Sabiales | Sabiaceae |
| Salviniales | Azollaceae Marsileaceae Salviniaceae |
| Santalales | Balanophoraceae Eremolepidaceae Loranthaceae Misodendraceae Olacaceae Opiliaceae Santalaceae Viscaceae |
| Sapindales | Aceraceae Anacardiaceae Burseraceae Meliaceae Pilocarpaceae Rutaceae Sapindaceae Simaroubaceae |
| Saxifragales | Crassulaceae Grossulariaceae Haloragaceae Saxifragaceae |
| Schizaeales | Schizaeaceae |
| Selaginellales | Selaginellaceae |
| Solanales | Convolvulaceae Cuscutaceae Hydroleaceae Nolanaceae Sclerophylacaceae Solanaceae Sphenocleaceae |
