Cancellus is a genus of hermit crabs in the family Diogenidae.

[1] Members of this genus are most commonly found living in small crevices in the outer continental shelf at mesophotic depths.

They can be found living in rocks, sponges, and algae among other places.

The genus has a cosmopolitan distribution.

Four species are known from the western Atlantic (C. heatherae, C. ornatus, C. viridis, and C.