The male southern red bishop has eclipse plumage, meaning it changes colour during the breeding season. Breeding males are brightly coloured, with the upperparts being red to orange, with brown wings and tail.
The upper chest and under tail coverts are red to orange, with the breast and belly black. The head is red, with a black face. Both male and female have a thick conical seed eater bill.
Outside of the mating season, both the male and female are similar in appearance, with a streaky brown plumage and a pale chest. The male is slightly larger than the female, who is around 13 cm in length.
The southern red bishop is a polygynous species with the male taking more than one female simultaneously and or consecutively, but without assisting with the incubation or rearing of the chicks.
The male does defend his territory against other males.
At the start of the breeding season, the male will build a number of nests in his territory to attract females and he displays this with a conspicuous flight called a bumble bee flight, with his feathers all ruffled up.
The nest is oval in shape and woven out of grass, normally built over water. The female will lay two to four eggs.