Brunei Darussalam (B), Indonesia (B), Malaysia (B), Thailand (B).
Southern Thailand, Peninsular Malaysia, northern and south-eastern Sumatra (Aceh, Sumatera Utara, Lampung), Lingga Archipelago, Belitung and Borneo.
 
Population
Estimated population is unknown (2010) and decreasing.
Status NT
Habitat destruction and degradation due to illegal logging and land conversion, and forest fires, are the main threats.
For more information see BirdLife International Species Factsheet.
Scarlet-breasted Flowerpecker (Prionochilus thoracicus) [XC335905]
by Jason Bugay Reyes from Mersing (near Endau), Johor, Malaysia (call)
Scarlet-breasted Flowerpecker (Prionochilus thoracicus) [XC428454]
by Jason Bugay Reyes from Klias Forest Reserve, Beaufort, Sabah, Malaysia (call, song)
Subspecies
No subspecies.
An undescribed subspecies may exist in Riau Archipelago.