Tourist visa - general information.

Entry Visas: Estonia,Latvia,Lithuania tourist visa is not required for citizens of United States for a stay up to 90 days! Invitation letters are NOT necessary for citizens of US and Canada for obtaining official, business, private, cultural, and sports visas.
If you are going to visit Russia or Kaliningrad Oblast, the Russian exclave between Poland and Lithuania on the Baltic Sea from any of the baltic states, you will also need a Russian visa.
But please check the following:
Check if your passport valid for at least 90 days following your departure date. However, it's strongly recommended to travel with 6 months validity on your passport at all times.
Check, if your passport has blank Visa pages.
And most importantly, confirm if transit visa is required for any connections.Check with your airline in case you have connecting flights overseas as part of your journey to Ukraine.

Useful Links:

Consular Office of Estonia in the USA.
Consular Office of Latvia in the USA.
Consular Office of Lithuania in the USA.

Please contact us on any visa questions.