Although this hermit crab species generally inhabits the discarded shell of a free-living gastropod mollusc, it sometimes makes use of the empty, tube-like shells of certain gastropod mollusc species while the tube is permanently cemented to rocks in the reef.

[3] As a hermit crab, Calcinus verrillii needs to find suitable empty shells of gastropod molluscs in which to live as it grows.

On some occasions the hermit crab takes up abode in the calcified tube of the vermetid gastropod Spiroglyphus irregularis.

[3] The advantages to the crab in making use of such a tube-like shell is that it is less likely to be swept off the rocks by strong water movements, and plenty of food may be brought to it by the current.

[3] Female C. verrillii grow larger than males, and are more likely to occupy tube shells.