The bright crimson colour of the adult Crimson Rosella is very different to the olive-green plumage of juvenile birds. The body is mostly red, while the cheek and upperwing have blue patches. The upperparts and remainder of wings are black with red edges.
They are commonly seen during the winter months, but may be seen at any time on the year. Unlike some parrots, they have a pleasant bell like call. They nest in tree hollows located high in trees. The female incubates the eggs alone but both sexes care for the chicks. They predominantly feed on the seeds of eucalypts, grasses and shrubs.