Czech Republic has been a member of both the European Union and the Schengen area.
Citizens of countries that are also in the European Union and the Schengen area may stay in the Czech Republic with no permit requirements. They only need a valid travel document or an ID card. If anyone stays in the Czech Republic longer than three months, he or she must notify the relevant authorities of their stay.
The list of countries whose citizens may travel for a short term to the Czech Republic with only a valid travel document, without a visa, can be found here.
The list of countries whose citizens must have a relevant valid visa to enter the Czech Republic can be found here.