Kauce

Kauce (also called jistota in legal documents) is a security deposit you pay at the start of a Czech lease. The landlord holds it for the duration of the rental and returns it after you move out, minus any damages and unpaid utilities.

Czech law caps the deposit at three months' rent. Most Prague landlords ask for two months. The landlord has 30 days from the end of the lease to return it. Document the flat's condition with photos on move-in day. It's your single best protection against deposit disputes.