It is possible to take your SIXT rental car on ferries between Greek islands, but not internationally. If you plan to take your car on a ferry, please ask an agent about additional protection for your rental car, as regular coverage is not valid for ferry travel.
You must have a valid driver’s license for 1 year along with an ID or passport to rent a car with SIXT. If your license is from outside the EU, you also need an international driving permit.
You must be at least 21 years old with a valid license held for 1 year to for a SIXT car rental in Greece. Some car categories have a higher minimum age, and an underage driver fee applies to renters under 23.