Do you need an International Driving Permit for Greece?

The US Embassy states that US citizen tourists and temporary residents staying under six months may drive on a valid US license. It still advises carrying an IDP, for two practical reasons rather than a legal one.

First, rental companies may require an IDP before releasing a car regardless of the legal position. Second, the embassy notes an IDP may be necessary in the event of an accident. Driving and licensing rules are set solely by the Greek authorities, so confirm current requirements with a Greek consulate before you travel.

An International Driving Permit is a translation of your licence into a standard multilingual booklet, issued under the 1949 and 1968 road traffic conventions. It is not a licence, and it is never valid on its own: you carry it with your own licence, and police expect to see both.

It is issued against the vehicle classes already on your home licence, and it never adds one. If your licence does not cover motorcycles, an IDP does not let you ride a scooter in Greece; if it does not cover a heavier vehicle, the permit will not cover a camper or a minibus either. The permit restates what you already hold, in a form the local authorities can read.