Entering and leaving Ukraine is no longer a problem for most visitors since the country became an independent nation. If you are a citizen of the United States, the European Union, Swiss Confederation, Liechtenstein, Canada, and Japan, you no longer need a visa if you are not going to be in the country for 90 days or less. To be sure that the law has not changed since it was instituted in 2005, you should confirm 
this information with the Ukrainian Consulate in your home country before travelling.
When you enter or leave Ukraine, you should pass through the green or red custom corridors. Always have your travel papers available for inspection including any paperwork that you receive and fill out when going through customs into the country. You will need them in order to leave. Also, always make sure that you have all of your paperwork before leaving the customs area to make sure they have been properly returned to you.
If you are carrying goods or money that needs to be declared you will need to pass through the red corridor. These items include: prohibited items such as explosives, weapons that are not approved by the authorities; drugs; artwork; antiques; luggage that is being sent through separately; more than $1,000 and 85 hryvnyas in cash; personal jewellery that exceeds $240 in value; more than 1 litre of alcoholic beverages; and more than 200 grams of tobacco products. Everyone else should us the green customs corridor.
All foreign visitors are required to have insurance policies in place that guarantee payment if any medical treatment is provided to them. These policies can be bought in Ukraine from the State JSC for Providing the Foreign Citizens with Emergency Aid or any place where a visa is processed and at the state border during crossing.
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