The Estonian language has six locative cases, descended from the locative cases of Proto-Finnic. They can be classified according to a three-way contrast of entering, residing in, and exiting a state, with two sets of cases: inner and outer.

For some nouns, there are two forms of the illative: the regular suffix -sse (e.g. keelesse), added to the genitive stem, and an alternative, short form, which is either consists of a different suffix (keel > keelde), lengthening (e.g. maja > majja, [ko:l] > [ko::li]), and/or another change in the word. The always regular -sse illative ending is a newer innovation, and can sometimes have a slightly different meaning than the old "short form" illative, the latter having the concrete locative meaning (e.g.: tuppa 'into the room'), and the former being used in other structures that require the illative (mis puutub toasse 'concerning the room...').^[1]

• Proto-Finnic locative system
• Finnish locative system

• Moseley, C. (1994). Colloquial Estonian: A Complete Language Course. London: Routledge.
• Oinas, Felix J (1966). Basic Course in Estonian. Bloomington: Indiana University.
• Estonian Language - Estonian Institute
• The Estonian Language Blog
• Eesti keele käsiraamat - Käändsõna