EU and EEA citizens do not need a visa or work permit. However, they must apply for residence permit/ID card if the length of stay exceeds three months. You must register within three months and you will be granted temporary residency. Go to the Estonian Ministry of the Interior for more information.
Non-EU or EEA citizens may require a visa or work permit. Some are eligible to work without a visa for up to three months in a six-month period, though they must register for short-term work. Check the arrangements between your home country and Estonia. Visit the Estonian Embassy website for details. More information is also available through the Police and Border Guard Estonia .