The rump is greyish-brown, the uppertail coverts metallic purple and the tail black, glossed blue.

There is a narrow purple collar beneath the metallic green throat, above a scarlet breast and pale brown belly.

[4] Mitochondrial data place this species as being most closely related to the southern double-collared sunbird C. chalybea of South Africa, though more research is warranted to confirm this relationship.

This shift is due to the fact that golden-winged sunbird Drepanorhynchus reichenowi has taxonomic priority when also included in Nectarinia.

The northern double-collared sunbird is often found in small mixed-species flocks, associating with species like white-eyes (genus Zosterops) and the oriole finch (Linurgus olivaceus).

It is aggressive throughout the year and attacks con-specific males, sometimes resulting in mid-air fights which may continue on the ground.

[3] The northern double-collared sunbird is a common species with a very wide range, and the population trend is thought to be steady.