It shares many features with the ancient Xiongnu[5] and Jie languages,[6] and according to Alexander Vovin, Edward Vajda, and Étienne de la Vaissière, is closely related to them.

It is poorly attested, the only available lexicon amounting to about 65 words, and some of them have been identified as being Yugh, not Pumpokol.

[7] It has traditionally been viewed as being grouped with Arin in an Arin-Pumpokol subfamily of Southern Yeniseian, but Vajda 2024 challenges this, stating that "Arin, Pumpokol and Kott-Assan display no shared innovations to suport them as an opposite "'Southern Yeniseian' branch" of Yeniseian, reflecting only their geographical position rather than a genealogical grouping.

[3] According to O. Tailleur, it should be considered a dialect of the Ket language, as most materials labeled 'Pumpokol' are in reality of Ketic affiliation, not Pumpokol.

Sibilant phonemes are absent in words of native Yeniseian origin.