Peasiella tantilla is a species of sea snail, a marine gastropod mollusk in the family Littorinidae, the winkles or periwinkles.

[2] The shell of Peasiella tantilla is a spiral shape and its body symmetry is "dextrally coiled".

[3] Their shell also extends all the way down to the base and tends to be light brown to yellow.

Peasiella tantilla is abundant along the coast of the supratidal region where they are commonly found in pools and are close to the sea.

[2] Examples of places they occur are the Hawaiian Islands, Oceania, Indo-China, and Indo-Malaysia.