Similarly to Nicola, there is very limited documentation on Tsetsaut. Consequently, it is difficult to place it in the family with much certainty. Athabaskanists have concluded that it is a Northern Athabaskan language consistent with its geographical occurrence, and that it might have some relation to its distant neighbor Tahltan. Tsetsaut, however, shares its primary hydronymic suffix ("river, stream") with Sekani, Beaver, and Tsuut'ina – PA *-ɢah – rather than with that of Tahltan, Tagish, Kaska, and North and South Tutchone – PA *-tuʼ (Kari 1996; Kari, Fall, & Pete 2003:39). The ambiguity surrounding Tsetsaut is why it is placed in its own subgroup in the Rice–Goddard–Mithun classification.