| Croton strigosus Spreng., 1822 |
| Croton stylosus Müll. Arg., 1865 |
| Croton suaveolens Torr., 1858 |
| Croton subcapitatus Müll. Arg., 1874 |
| Croton suberosus Kunth, 1817 |
| Croton subfragilis Müll. Arg., 1865 |
| Croton subjucundus Croizat, 1942 |
| Croton subtomentosus L., 1759 |
| Croton sutup Lundell, 1940 |
| Croton sylvaticus Schltdl., 1846 |
| Croton tabascensis Lundell, 1940 |
| Croton tacanensis Lundell, 1940 |
| Croton tenuilobus S. Watson, 1886 |
| Croton tenuis S. Watson, 1879 |
| Croton texensis (Klotzsch) Müll. Arg., 1866 |
| Croton texensis var. utahensis Cronquist, 1992 |
| Croton tomentosus Link, 1822 |
| Croton torreyanus Müll. Arg., 1866 |
| Croton tragioides S.F. Blake, 1922 |
| Croton tremulifolius Croizat, 1940 |