It is closely related to the common starling (S. vulgaris), but has a much more restricted range, confined to the Iberian Peninsula, Northwest Africa, southernmost France, and the islands of Sicily, Corsica and Sardinia.

[2][3] The adult spotless starling is very similar to the common starling, but marginally larger (21–23 cm length; 70–100 g weight), and has darker, oily-looking black plumage, slightly purple- or green-glossed in bright light, which is entirely spotless in spring and summer, and only with very small pale spots in winter plumage, formed by the pale tips of the feathers.

It also differs in having conspicuously longer throat feathers (twice the length of those on common starlings[2]), forming a shaggy "beard" which is particularly obvious when the bird is singing.

[4] The spotless starling uses a wide range of habitats and can be found in any reasonably open environment, from farmland and olive groves to human habitation.

[3][8] The population has grown in recent decades with a northward expansion in range, spreading to the whole of Spain (previously absent from the northeast) between 1950 and 1980, and colonising locally along the southern coast of mainland France since 1983.