This is dependent on which region or country you want to hire a vehicle. Although several European nations and the states of New York and Michigan in the United States allow you to hire a vehicle at the age of 18, numerous localities require you to be 21. Before placing a purchase, double-check the minimum age requirements for each country. For renters under the age of 25, most rental businesses impose an extra Young Driver Fee, however, the age varies by firm and area.