Internal diversity suggests that the family broke up about 3,000 years ago. North Bahnaric is characterized by a register contrast between breathy and modal voice, which in Sedang has tensed to become modal–creaky voice.
Lamam is a clan name of the neighboring Tampuon and Kaco’.
Sidwell (2009) tentatively classifies the Bahnaric languages into four branches, with Cua (Kor) classified independently as East Bahnaric.
Other Northern Bahnaric languages, too poorly known to classify further, are Duan and Katua.
West Bahnaric is a dialect chain to the west of North Bahnaric, Unlike the other Bahnaric languages to the east, the West Bahnaric languages were under Khmer rather than Chamic influence, and also by the Katuic languages as part of a Katuic-West Bahnaric sprachbund (Sidwell 2003).
Sidwell (2003) proposes the following West Bahnaric groupings, with Lavi branching off first, Jru'/Laven, Su', and Juk as forming a branch that had branched off secondarily, and the rest within a core group. Jru' and Brao each have tens of thousands of speakers, while the other languages have no more than 1,000 speakers each.
Kassang is a Bahnaric language (Sidwell 2003), though Ethnologue lists it as Katuic.
Sidwell (2002, quoted in Sidwell 2003) gives the following classification for the Central Bahnaric languages. Note that Sidwell (2009) later classifies Cua as an independent branch, namely East Bahnaric.