The Spanish Sparrow is distinguished from the House Sparrow by its entirely chestnut crown and, most notably, by the dense black streaking that covers its breast and flanks, giving it a much darker appearance. The females, however, are almost indistinguishable from those of the House Sparrow.

In Extremadura, its habitat is very specific: it prefers wetlands, irrigated areas, and riverside woodlands, where it typically establishes massive breeding colonies in large stick nests. It is a resident species, although it undergoes significant local movements. It is a characteristic inhabitant of Extremaduran fluvial and agricultural ecosystems.