Stay in Estonia and other Schengen Member States is short term stay, if it does not exceed 90 days during any 180day period. Third country nationals can execute short-term stay in Schengen on the basis of
If the intended stay of the third country national in Estonia is longer than 90 days during 180day period, person must apply for a document permitting long stay in Estonia – D-visa or residence permit. More information about long term stay can be found here.