Mountains in south-eastern Nigeria, north-western Cameroon, western Angola (Mt Moco); Bioko (Fernando Póo); also Albertine Rift in eastern Zaire, western Uganda, Rwanda and Burundi, and mountains in Kenya, Tanzania, north-eastern Zambia, Malawi and northern Mozambique (Mt Namuli).
 
Population
Estimated population is unknown (2010).
Bar-tailed Trogon (Apaloderma vittatum) [XC860453]
by Louis A. Hansen, Henrik Kisbye, Louise Pedersen, Marcel Rahner, the late Jens Otto Svendsen from Evergreen Forest Patches, Nyika NP, Northern Region, Malawi (song)
Bar-tailed Trogon (Apaloderma vittatum) [XC872441]
by The late Jens O. Svendsen and Louis A. Hansen from Castle Forest, Mount Kenya, Kirinyaga County, Kenya (song)
Subspecies
Population in western half of Africa sometimes separated subspecifically as camerunense, and birds from Bioko (Fernando Póo) occasionally further separated as francisci, but characters apparently not constant for either of these forms.
The following 2 subspecies are recognised:
vittatum Shelley, 1882 - South-eastern Nigeria and western Cameroon; central Angola; Uganda and eastern DR Congo; Kenya to Mozambique.
camerunensis Reichenow, 1902 - Nigeria, Cameroon, and Bioko to Angola, western Democratic Republic of the Congo, and western Uganda.