The plum-headed parakeet is a mainly green parrot, 33 cm long with a tail up to 22 cm.
The male has a red head which shades to purple-blue on the back of the crown, nape and cheeks while the female has blueish-gray head.
There is a narrow black neck collar with verdigris below on the nape and a black chin stripe that extends from the lower mandible.
There is a red shoulder patch and the rump and tail are bluish-green, the latter tipped white.
The upper mandible is orangish-yellow, and the lower mandible is dark.
The female has a dull bluish grey head and lacks the black and verdigris collar which is replaced by yellow.
The upper-mandible is corn-yellow and there is no black chin stripe or red shoulder patch.
Immature birds have a green head and both mandibles are yellowish.
The dark head is acquired after a year.
The delicate bluish red appearance resembling the bloom of a peach is produced by a combination of blue from the optical effects produced by the rami of the feather and a red pigment in the barbules.

Some authors have considered the species to have two subspecies, the nominate from peninsular India (type locality restricted to Gingee) and the population from the foothills of the Himalayas as bengalensis on the basis of the colour of the head in the male which is more red and less blue.
Newer works consider the species to be monotypic.

The different head colour and the white tip to the tail distinguish this species from the similar blossom-headed parakeet (Psittacula roseata).
The shoulder patch is maroon coloured and the shorter tail is tipped yellow in P. roseata.


A supposed species of parakeet, the so-called intermediate parakeet Psittacula intermedia is thought to be a hybrid of this and the slaty-headed parakeet (Psittacula himalayana).
The plum-headed parakeet is a mainly green parrot, 33 cm long with a tail up to 22 cm. The male has a red head which shades to purple-blue on the back of the crown, nape and cheeks while the female has blueish-gray head. There is a narrow black neck collar with verdigris below on the nape and a black chin stripe that extends from the lower mandible. There is a red shoulder patch and the rump and tail are bluish-green, the latter tipped white. The upper mandible is orangish-yellow, and the lower mandible is dark. The female has a dull bluish grey head and lacks the black and verdigris collar which is replaced by yellow. The upper-mandible is corn-yellow and there is no black chin stripe or red shoulder patch. Immature birds have a green head and both mandibles are yellowish. The dark head is acquired after a year. The delicate bluish red appearance resembling the bloom of a peach is produced by a combination of blue from the optical effects produced by the rami of the feather and a red pigment in the barbules.
Some authors have considered the species to have two subspecies, the nominate from peninsular India (type locality restricted to Gingee) and the population from the foothills of the Himalayas as bengalensis on the basis of the colour of the head in the male which is more red and less blue. Newer works consider the species to be monotypic.
The different head colour and the white tip to the tail distinguish this species from the similar blossom-headed parakeet (Psittacula roseata). The shoulder patch is maroon coloured and the shorter tail is tipped yellow in P. roseata.

A supposed species of parakeet, the so-called intermediate parakeet Psittacula intermedia is thought to be a hybrid of this and the slaty-headed parakeet (Psittacula himalayana).
Plum-headed parakeet