The Problem
You loved your time in Turkey so much that you lost track of the days, or a sudden medical emergency prevented you from flying home. Now, you realize your 90-day tourist visa (or e-Visa) has expired, and you are technically in the country illegally.
How the Law Works in Turkey
Turkish immigration laws strictly regulate the duration of stay for foreigners. Staying even one day past your visa limit is considered a "Visa Violation" (Vize İhlali). The law states that overstayers must pay an administrative fine upon exiting the country. The fine amount is not fixed; it is calculated based on your nationality and the exact number of days you overstayed.
What the Tourist Should Do
Do not try to sneak out of the country. Go to the airport earlier than usual on your departure day and head straight to the "Visa Violation Office" (Vize İhlal Ofisi) before going through passport control. Pay the fine in cash (usually accepted in Turkish Lira, so have cash ready).
The Risks
If you refuse to pay the fine at the airport, or if you cannot afford it at that moment, you will be allowed to leave, but you will automatically receive an entry ban to Turkey ranging from 1 to 5 years. If your overstay is extremely long (e.g., several months or years), paying the fine might not save you from a ban, and you risk deportation if caught by police before reaching the airport.
LetFix Solution
Visa calculations, entry bans (Tahdit Kodları), and deportation orders are highly complex legal matters. If you are facing a massive overstay fine, want to appeal an entry ban, or need to quickly apply for a residence permit to legalize your status, expert immigration lawyers are essential.

