The 13cm male Moussier's Redstart has a black head with a broad white stripe running above each eye and down the side of the neck. The upperparts are black other than a white wing patch, and the rich chestnut tail, from which it and other redstarts get their names (start is an old word for tail). The underparts are a rich orange-red.
The smaller, shorter-tailed female has a pale brown head and upperparts, and the underparts are a paler orange than the male, although generally redder than the underparts of the similar but slightly larger female Common Redstart.
This species has a large range, with an estimated global Extent of Occurrence of 400,000 kmē. The global population size has not been quantified, but it is believed to be large as the species is described as 'frequent' in at least parts of its range (Keith et al. 1992). Global population trends have not been quantified, but the species is not believed to approach the thresholds for the population decline criterion of the IUCN Red List (i.e. declining more than 30% in ten years or three generations). For these reasons, the species is evaluated as Least Concern.