It is a common practice in Greece for hotel staff to ask for your passport at check-in, but they are generally not allowed to keep it for more than a short period. Under Greek law, hotels are required to record the details of all foreign guests for police and national statistics, which involves noting your name, passport number, and nationality. In the past, some hotels would hold passports behind the desk until checkout to ensure payment, but this is now largely discouraged and technically improper. Most modern hotels will simply take a photocopy or scan of your passport's information page and return the original to you immediately. If a smaller guesthouse asks to hold it "overnight" to process the paperwork, you are well within your rights to ask them to do it while you wait or to offer a copy instead. For security and peace of mind, you should always keep your physical passport in your possession or in the hotel room safe. As of 2026, many Greek hotels are transitioning to digital registration systems that allow you to upload your details in advance, further reducing the need for physical passport handling at the front desk.