Soon all of Yatvingans were assimilated by Lithuanians and forgot their language with only dialectal differences left. Nowadays, though some revival is noticed, as well as research and reconstruction work is carried out, Sudovian is considered a dead, extinct language.

It was an archaic East Baltic tongue, similar to Old Prussian and Lithuanian. It has both long and short vowels, a rich collection of diphthongs and sibilant consonant like in other Baltic languages. The stress is very complicated: Sudovian had the same four nominal accent classes as does Lithuanian, but it retained the original accentual state of Baltic (an acute rising accent and a circumflex falling accent). The first class is the acute baritone paradigm. The second is the circumflex baritone paradigm. Thirdly, the acute mobile paradigm. Lastly, the circumflex mobile paradigm. Four or five noun cases are the same as in Old Prussian: nominative, genitive, dative, accusative, vocative. The noun declension is very conservative and preserved many features from the Indo-European stage. Sudovian verbs have three simple tenses, 3 or 4 moods and a large number of verbal nouns as participles and infinitive.

Sudovian dialects of the Lithuanian language is now spoken in the region of Suvalki in Poland. We can offer some links to those people who still work trying to renovate the language of the past.