We explain and explore class-theoretic potentialism—the view that one can always individuate more classes over a set-theoretic universe. We examine some motivations for class-theoretic potentialism, before proving some results concerning the relevant potentialist systems (in particular exhibiting failures of the
$\mathsf {.2}$
and
$\mathsf {.3}$
axioms). We then discuss the significance of these results for the different kinds of class-theoretic potentialists.