The lexicon of certain Tharu households is indicative of an archaic, 'indigenous' substratum, potentially predating both Sino-Tibetan or Indo-Aryan settlement.

[7] Tharu communities in different parts of Nepal and India do not share the same language like the other ethnic groups as it varies between the eastern, central and western Terai.

[16] Kochila Tharu communities are not found in isolation, but live in districts intermixed with speakers of other languages.

[22] At local level, Tharu has official status in Ghorahi sub-metropolitan city of Dang district.

[23][24][25] In Nepal Tharu languages are spoken throughout the Terai region from Mechi river in the east to Mahakali river in the west in following districts:[19][26] With an increase in internal migrants and international emigration Tharu-speaking people have emerged in every district of Nepal and various countries such as the US, Japan, Qatar, UAE and Australia.

[30] In Uttar Pradesh it is spoken in Lakhimpur Kheri, Balrampur, Shravasti, Gorakhpur, Basti, Bahraich and Gonda districts.